By ShipCalculators.com · Published 9 May 2026 · last updated 7 June 2026

Antigua Convention 2002: NE Pacific Marine Environment

The Convention for Cooperation in the Protection and Sustainable Development of the Marine and Coastal Environment of the Northeast Pacific, universally called the Antigua Convention after the city of its signature, was adopted at Antigua, Guatemala on 18 February 2002. As of 2026, the Convention has not yet entered into force: it was opened for signature to the coastal states of the Northeast Pacific region but has not obtained the ratifications required to trigger entry into force under Article 31. The seven prospective Contracting Parties are Colombia, Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua, and Panama. The Convention is administered in the interim by a Secretariat coordinated through the UNEP Regional Office for Latin America and the Caribbean in cooperation with the UNEP Caribbean Environment Programme (UNEP-CEP), with preparatory meetings rotating among the prospective Parties and regional support from San Jose, Costa Rica. The Antigua Convention is notable among the UNEP Regional Seas conventions in that, as of 2026, no implementing Protocols have been adopted and the parent Convention itself is not yet in force, leaving the Northeast Pacific region without a binding regional environmental treaty comparable to the Lima Convention 1981 to its south or the Cartagena Convention 1983 covering the Caribbean sides of the same states. The Convention area covers the Pacific coast of Central America and northwest South America, a coastline of approximately 6,500 km from the US-Mexico maritime boundary at approximately 32 degrees N to the Colombia-Panama maritime boundary at approximately 7 degrees N, encompassing the Eastern Tropical Pacific with its high biological productivity, its hammerhead-shark and humpback-whale aggregations, its world-renowned offshore islands (Cocos Island in Costa Rica at 18,950 km squared and Coiba National Park in Panama, both UNESCO World Heritage sites), and the Pacific approach to the Panama Canal. The Convention sits alongside but does not duplicate the IMO instruments: it complements the MARPOL Convention, the MARPOL Annex I oil pollution prevention regime and the Reg 15 oil discharge criteria, the Ballast Water Management Convention and the global PSSA framework, and provides the intended regional umbrella for cooperation under IMO 2020 sulphur cap implementation along the Pacific coast of Central America. The basin contains no IMO PSSA designations and no MARPOL Special Areas as of 2026, with the only PSSA in the broader region (the Galapagos PSSA) sitting in the adjacent Lima Convention 1981 area in Ecuadorian waters.

Contents

Background: UNEP Regional Seas + the Northeast Pacific gap pre-2002

The Northeast Pacific basin is geographically distinctive among the UNEP Regional Seas Programmes: it is a long, narrow Pacific margin running along the western flank of Central America and the northwestern coast of South America, with no closed-sea geometry and no continental shelf comparable to the wider Caribbean to the east. The basin is bounded to the north by the US-Mexico maritime boundary at approximately 32 degrees N, to the east by the Sierra Madre and the Central American volcanic isthmus that walls off the Pacific drainage from the Caribbean drainage, to the south by the Colombia-Panama maritime boundary at approximately 7 degrees N which separates the Antigua Convention area from the Lima Convention 1981 area, and to the west by the East Pacific Rise and the open Pacific gyre.

The institutional architecture for cooperation in this basin lagged the rest of the UNEP Regional Seas portfolio by more than two decades. The UNEP Regional Seas Programme was launched in 1974 with the Mediterranean Action Plan, with the Barcelona Convention 1976/1995 signed in February 1976. Through the late 1970s and 1980s, UNEP successively negotiated the Kuwait Convention 1978, the Abidjan Convention 1981, the Lima Convention 1981, the Jeddah Convention 1982, the Cartagena Convention 1983 and the Nairobi Convention 1985, covering the principal regional seas of the global ocean. By the close of the 1980s, the Northeast Pacific was one of the remaining gaps in the global Regional Seas architecture, with no binding regional environmental Convention covering the Pacific coast of Central America and northwestern South America.

The reasons for the delay are partly geographical and partly political. Geographically, the Pacific coast of the Convention area is a relatively short envelope, around 6,500 km in aggregate, with no closed-sea oceanographic distinctiveness. Several of the Central American states had limited environmental administrative capacity through the 1980s. Politically, the Central American civil wars of the 1980s, in Nicaragua, El Salvador and Guatemala, drained political attention and donor capacity from environmental cooperation, and the Esquipulas peace process of 1986-1990 was preoccupied with conflict resolution rather than ocean governance. The Cartagena Convention 1983 covered the Caribbean side of many of the same states, providing partial regional coverage and reducing the urgency of negotiating a separate Pacific Convention.

By the late 1990s, with the Central American conflicts settled and with growing engagement in the UNEP Regional Seas framework, the conditions were ripe for the long-deferred Northeast Pacific Convention. UNEP launched preparatory consultations in 1999 through a series of expert meetings hosted in Costa Rica, Panama and other regional capitals, and a Conference of Plenipotentiaries was convened in Antigua, Guatemala in February 2002 to finalize the text.

Adoption at Antigua Guatemala, 18 February 2002

The Conference of Plenipotentiaries on the Protection and Sustainable Development of the Marine and Coastal Environment of the Northeast Pacific convened at Antigua, Guatemala on 16 to 18 February 2002. Antigua is the colonial capital of Guatemala, a UNESCO World Heritage Site at the foot of the Agua Volcano, chosen as the venue both for its symbolic central position in the Central American isthmus and for its UNESCO heritage which projected the environmental and cultural seriousness of the negotiation. The Conference was attended by ministerial-level delegations from the prospective Parties, by the UNEP Executive Director and by observer delegations from non-Party states with regional interests.

The Convention was adopted on the closing day, 18 February 2002, and opened for signature by the seven coastal states of the Northeast Pacific: Colombia, Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua, and Panama. These seven states constitute the full set of independent coastal states along the Pacific margin from the Colombia-Panama border to Guatemala and El Salvador. The Convention entered the international-treaty cycle from that date, subject to ratification or accession by the requisite number of states to trigger entry into force under Article 31.

Not yet in force as of 2026

As of 2026, the Antigua Convention has not yet entered into force. This is the most important legal status fact about the regime. Entry into force requires ratification or accession by the minimum number of states specified in Article 31 of the Convention text. Because the Convention has not entered into force, the elaborate machinery of Protocols, Conferences of the Parties, and formal Secretariat arrangements envisaged by the Convention framework cannot be fully activated. Cooperation among the prospective Parties proceeds through preparatory meetings and voluntary arrangements coordinated by UNEP, not through legally binding Convention structures.

The not-in-force status is the defining constraint on the Antigua Convention regime in 2026. Every comparative analysis of the Convention against the Lima and Cartagena counterparts must begin with this fact: unlike those two conventions, which entered into force in 1986 and 1986 respectively, the Antigua Convention remains pre-entry-into-force more than two decades after adoption. The Convention text and its institutional ambitions remain a framework, not yet a binding legal instrument.

Ratification progress and the prospective parties

The seven prospective Contracting Parties are, from north to south along the Pacific coast: Colombia, Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua, and Panama. UNEP’s published information on ratification progress for this Convention should be consulted for the current deposit count; the article does not speculate on individual state ratification dates beyond what UNEP publicly reports.

The slow progress toward entry into force reflects a combination of structural factors common to low-capacity multi-state treaty regimes in the developing world: competing legislative priorities, limited domestic environmental constituency for marine issues, limited administrative capacity to assess compliance obligations before ratifying, and the absence of a triggering incident (a major regional pollution event) that would have galvanized political attention. The overlap with the Cartagena Convention regime, which already covers the Caribbean side of all seven prospective Antigua Parties except Colombia’s Pacific-only exposure, reduced the perceived urgency of a parallel Pacific instrument.

Colombia’s inclusion as a prospective Party distinguishes the Antigua Convention from the Cartagena Convention for that country: Colombia is a Party to the Cartagena Convention 1983 for its Caribbean waters and a prospective Party to the Antigua Convention for its Pacific waters on the northern Pacific coast below Panama. Colombia is also a Party to the Lima Convention 1981 for its South-East Pacific waters, making it one of the few states in the regional-seas system simultaneously prospective or actual Party to three regional-seas instruments covering adjacent Pacific and Caribbean waters.

The 7 prospective contracting parties

The seven prospective Contracting Parties span the Pacific margin of Central America and northwest South America. Listed from north to south along the Pacific coast:

Guatemala holds a Pacific coastline of approximately 254 km from the Suchiate River boundary with Mexico (approximately 14.5 degrees N) to the Rio Paz boundary with El Salvador, dominated by the Puerto Quetzal port complex. Guatemala is dual-coast: Pacific waters fall under the Antigua Convention area while Caribbean and Gulf Honduras waters fall under the Cartagena Convention 1983 area.

El Salvador holds a Pacific frontage of approximately 307 km from the Rio Paz boundary with Guatemala to the Gulf of Fonseca boundary with Honduras, with the Acajutla port and the Bahia de Jiquilisco mangrove system as principal features. El Salvador is purely Pacific-coast with no Caribbean coastline and is therefore a prospective Party to the Antigua Convention only.

Honduras holds a short Pacific frontage of approximately 153 km on the Gulf of Fonseca, a tri-national gulf shared with El Salvador and Nicaragua, with the San Lorenzo and Henecan port complexes. Honduras is dual-coast and is a Party to the Cartagena Convention for its Caribbean and Gulf of Honduras waters.

Nicaragua holds a Pacific coast of approximately 350 km from the Gulf of Fonseca to the Costa Rican boundary at the Bahia de Salinas, with the Corinto port and the Cosiguina volcanic peninsula as principal features. Nicaragua is dual-coast and is a Cartagena Convention Party for its Caribbean waters.

Costa Rica holds a Pacific coast of approximately 1,016 km of indented tropical coast through the Gulf of Papagayo, the Gulf of Nicoya, the Quepos-Manuel Antonio zone, the Osa Peninsula and the Golfito-Burica region, with the offshore Cocos Island at 5.5 degrees N, 87 degrees W. Costa Rica is dual-coast.

Panama holds the longest Central American Pacific coast at approximately 1,700 km from the Costa Rican boundary at Punta Burica through the Gulf of Chiriqui, the Gulf of Montijo, the Coiba archipelago, the Gulf of Panama, the Las Perlas archipelago and the Darien Pacific to the Colombian boundary at Cabo Tiburon. Panama is dual-coast and is simultaneously a Party to the Lima Convention 1981 for its southern Pacific border with Colombia.

Colombia holds the northern Pacific coast between Panama and Ecuador, bringing the southern boundary of the Antigua Convention area to approximately 7 degrees N at the Colombia-Ecuador EEZ boundary (though Convention Article 1 establishes the boundary at the Colombia-Panama maritime boundary). Colombia is also a Party to the Cartagena Convention for its Caribbean waters and to the Lima Convention for its South-East Pacific coast south of Panama, making it the most multi-Convention Pacific-Caribbean state in the system.

The seven prospective Parties divide into three sub-regional clusters by capacity and geography. Guatemala, El Salvador, and Honduras form the Northern Triangle bloc with Pacific coastlines under 350 km, lower environmental ministry capacity, and high vulnerability to tropical storms. Nicaragua, Costa Rica, and Panama form the Southern Central American bloc with stronger environmental administration and longer Pacific coastlines. Colombia stands apart as a South American state whose Pacific engagement in the Antigua Convention complements its Lima and Cartagena treaty portfolios.

Geographical scope: ~6,500 km Pacific coast

The Convention area is defined in Article 1 of the Convention as the marine environment, coastal zones and related inland waters of the Northeast Pacific from the southern boundary of the prospective Parties to the north, with a seaward extent corresponding to the Exclusive Economic Zones of each Party under UNCLOS. The aggregate Pacific coastline of the seven prospective Parties runs for approximately 6,500 km.

The coastline is geomorphologically varied across its latitudinal extent:

The Guatemalan Pacific coast runs approximately 254 km from the Suchiate River at the Mexico boundary south to the Rio Paz at the El Salvador boundary, with Puerto Quetzal as the principal port complex and the volcanic Sierra Madre de Chiapas descending steeply to a narrow coastal plain.
The Salvadoran coast is a 307 km Pacific frontage, with the Acajutla port and the Bahia de Jiquilisco mangrove system as principal ecological and commercial features.
The Honduran Pacific frontage is a 153 km envelope on the Gulf of Fonseca, shared tri-nationally with El Salvador and Nicaragua, with the San Lorenzo and Henecan port complexes serving a shallow-draft inshore trade.
The Nicaraguan Pacific coast runs approximately 350 km from the Gulf of Fonseca south to the Costa Rican boundary, with the Corinto port and the Cosiguina volcanic peninsula.
The Costa Rican Pacific coast is approximately 1,016 km of indented tropical coast, with the Gulf of Nicoya, the Osa Peninsula and the offshore Cocos Island being the principal ecological features.
The Panamanian Pacific coast is approximately 1,700 km from the Costa Rican boundary through the Gulfs of Chiriqui and Panama to the Colombian boundary at Cabo Tiburon, encompassing the Pacific approach to the Panama Canal.
The Colombian Pacific coast north of Ecuador runs from the Panama border south, including the Darien coast, the Gulf of Uraba approach, and the Tumaco port complex before meeting the Lima Convention area boundary.

The aggregate Convention area is a predominantly tropical Pacific margin with a narrow arid sub-region in the Tehuantepec dry corridor and broadly humid tropical and equatorial conditions across the Central American and Colombian sectors.

Hydrography: Eastern Tropical Pacific

The dominant oceanographic feature of the Convention area is the Eastern Tropical Pacific (ETP) circulation system, the eastern boundary of the equatorial Pacific gyre and one of the most biologically productive tropical ocean envelopes on Earth. The ETP is bounded to the north by the California Current transitioning through the Mexican Pacific at around 22-25 degrees N, to the south by the Equatorial Counter-Current and the Humboldt Current at the Colombian-Ecuadorian boundary, to the east by the Central American and Colombian coasts, and to the west by the Eastern Pacific Warm Pool transition.

The ETP is characterized by a shallow thermocline (typically 30 to 80 metres deep, locally rising to 20 metres), strong wind-driven upwelling in three principal cells (the Tehuantepec Gulf, the Papagayo Gulf and the Panama Gulf) where seasonal trade-wind jets blow through the gaps in the Sierra Madre and drive offshore Ekman transport, and high biological productivity. The three upwelling gulfs are seasonal: the Tehuantepec and Papagayo cells are most active during boreal winter (November to April) when the trade winds intensify, while the Panama cell follows a more complex seasonal cycle.

The ETP supports a distinctive pelagic community dominated by yellowfin tuna (Thunnus albacares), bigeye tuna (Thunnus obesus), skipjack tuna (Katsuwonus pelamis), dorado (Coryphaena hippurus), sailfish (Istiophorus platypterus), striped marlin (Kajikia audax), whale sharks (Rhincodon typus) and the regionally iconic scalloped hammerhead shark (Sphyrna lewini) which aggregates seasonally at offshore seamounts including the Cocos and Malpelo islands. The basin is also a critical migratory corridor for humpback whales (Megaptera novaeangliae) which migrate between Antarctic feeding grounds and breeding grounds in the Bahia Malaga of Colombia, the Gulf of Chiriqui of Panama and the Golfo Dulce of Costa Rica during the austral winter (June to October).

The ETP also experiences El Nino-Southern Oscillation (ENSO) impact. In the ETP, El Nino deepens the thermocline, suppresses the upwelling in the three coastal gulfs, weakens the productivity-driven food chain and triggers regional drought along the Pacific coast of Central America. La Nina conditions strengthen the upwelling and productivity but bring intensified rainfall and increased tropical-storm activity.

Major rivers: Lempa, Tempisque, Chagres, San Juan, Atrato

Riverine discharge to the Northeast Pacific is moderate by global standards. The Sierra Madre and the Central American volcanic chain prevent large catchment areas on the Pacific side, with the result that most major rivers of the Central American isthmus drain to the Caribbean (Atlantic) side rather than to the Pacific. The principal Pacific-draining rivers within the Antigua Convention area are:

The Lempa River, the largest river of Central America with an entirely Pacific drainage, rising in Guatemala and flowing through Honduras and El Salvador to discharge into the Pacific at the Bahia de Jiquilisco in El Salvador. The Lempa drains approximately 17,790 km squared and discharges around 230 cubic metres per second mean annual flow, with significant nutrient and sediment loading at the river mouth supporting the Jiquilisco mangrove system.
The Tempisque River of Costa Rica, draining the Guanacaste province to the Gulf of Nicoya, supporting the Pacific drylands and a Ramsar-listed wetland complex.
The Chagres River of Panama, the principal water source for the Panama Canal and one of the most operationally significant rivers in the global shipping system. The Gatun Lake (the artificial lake at the heart of the Canal) is fed by Chagres tributaries and is the source of the lockage water that lifts ships from sea level to 26 metres above sea level and back down.
The San Juan River of Nicaragua and Costa Rica, draining Lake Nicaragua to the Caribbean (not the Pacific), but regionally significant because the small Pacific drainage of Lake Nicaragua and its connection to the Caribbean side illustrates the low-watershed character of the Central American isthmus that made the Nicaragua route a historic canal alternative to Panama.
The Atrato River of Colombia, draining the Choco region to the Gulf of Uraba and the Caribbean, and the parallel Pacific-draining rivers of the Colombian Choco department including the San Juan de Micay and Baudo systems, which carry substantial freshwater, sediment and nutrient discharge to the northern Pacific coast of the Convention area.
The Balsas River of Mexico, a major river of southern Mexico that drains the central plateau and discharges to the Pacific at the Lazaro Cardenas port complex, is outside the formal Convention area (Mexico is not a prospective Antigua Party) but is noted here because the Convention area’s northern operational context often includes Mexican Pacific waters in regional reporting.

The aggregate riverine discharge within the Antigua Convention area is moderate, with the Lempa and the Colombian Choco rivers as the principal nutrient and sediment sources, and the Chagres as the operationally dominant river for the Panama Canal.

Secretariat: UNEP-CEP coordinated, San Jose, Costa Rica

The Convention preparations are administered through a coordination model run by UNEP through its Regional Office for Latin America and the Caribbean (ROLAC) based in Panama City and through the UNEP Caribbean Environment Programme (UNEP-CEP) based in Kingston, Jamaica. Because the Convention has not yet entered into force, a permanent dedicated Secretariat at a single host city comparable to the Lima Convention’s CPPS in Guayaquil or the Cartagena Convention’s UNEP-CEP in Kingston has not been formally established. Instead, substantive coordination is delivered through the existing UNEP-CEP machinery and through host-Party arrangements that rotate among the prospective Parties.

For most of the preparatory period, the operational coordination of the Antigua Convention preparatory process has been hosted with Costa Rican support in San Jose, Costa Rica, in partnership with the Costa Rican Ministry of Environment and Energy (MINAE) and the National System of Conservation Areas (SINAC). Costa Rica has projected itself as the natural regional environmental leader among the prospective Parties, with its strong environmental administrative tradition, its large protected-areas estate (around 26 percent of national territory in protected areas), and its hosting of the University for Peace and a network of regional environmental institutions.

Preparatory meetings of the prospective Parties (often styled as meetings of the Intergovernmental Meeting or Preparatory Committee under UNEP facilitation) have been convened periodically to advance Protocol drafting, resolve institutional questions, and encourage ratification by the prospective Parties. The funding model for this preparatory work relies on project funding from UNEP, the Global Environment Facility (GEF), the Inter-American Development Bank (IDB) and bilateral donors including Germany (GIZ), the United States (USAID through its environmental programmes) and Spain (AECID). The aggregate annual operating budget of the preparatory machinery is materially smaller than the Lima or Cartagena Convention Secretariats.

No protocols adopted as of 2026: framework-only situation

The single most distinctive feature of the Antigua Convention situation is the complete absence of adopted Protocols as of 2026, compounded by the non-entry-into-force of the parent Convention itself.

This situation is unique among the UNEP Regional Seas Conventions. Every convention in the Regional Seas family that has entered into force has at least one in-force Protocol. The Lima Convention 1981 has five Protocols in force; the Cartagena Convention 1983 has three in force (Oil Spills 1983, SPAW 1990, LBS 1999); the Barcelona Convention 1976/1995 has seven in force; the Nairobi Convention 1985 has three in force. The Antigua Convention is the only regime in the Regional Seas family where neither the parent Convention nor any Protocol has yet entered into force, leaving the Northeast Pacific without a binding regional marine-environmental treaty.

The absence of adopted Protocols reflects a combination of factors:

Non-entry-into-force of the parent Convention: Protocol negotiation proceeds most effectively within an established Convention framework with a standing Conference of the Parties. Without entry into force, the formal COP structure cannot convene under binding Convention rules, limiting the institutional authority to finalize Protocol texts.
Limited Secretariat capacity: the rotating-coordination model has constrained the ability to maintain sustained Protocol-drafting attention across preparatory cycles.
Overlap with the Cartagena Convention: six of the seven prospective Antigua Parties operate under Cartagena Protocols (Oil Spills 1983, SPAW 1990, LBS 1999) for their Caribbean waters. There has been a recurring debate about whether to negotiate new Antigua-specific Protocols or to extend the Cartagena Protocols to Pacific waters by amendment, with neither path yet resolved.
Lower political salience: in the absence of a major regional pollution incident or a high-profile fishery collapse comparable to the ENSO-driven Peruvian anchoveta collapses that drove the Lima Convention work programme, the political momentum for Protocol finalization has been weak.
Capacity heterogeneity across prospective Parties: the gap between Costa Rican and Colombian environmental ministry capacity at the high end and Guatemalan, Honduran and Salvadoran capacity at the low end has constrained the ability to reach Protocol-level commitments.

The work programme of the preparatory process has focused on expert-meeting drafting of three priority Protocols: an Oil Spills and Emergency Cooperation Protocol modelled on the Cartagena 1983 Oil Spills Protocol and the Lima 1981 Hydrocarbon Emergency Agreement, a Land-Based Sources of Pollution Protocol modelled on the Cartagena LBS Protocol of 1999 and the Lima Quito LBS Protocol of 1983, and a Specially Protected Areas and Wildlife Protocol modelled on the Cartagena SPAW Protocol of 1990. Draft texts of all three have been circulated in expert meetings and remain under preparatory consideration as of 2026, with no firm timeline for Convention entry into force or Protocol adoption.

Slow progress toward entry into force (2002-2026)

The 24-year gap between Convention adoption in February 2002 and non-entry-into-force as of 2026 is a defining feature of the regime. This duration exceeds that of any other UNEP regional-seas Convention: the Lima Convention entered into force five years after signature (1981-1986); the Cartagena Convention entered into force three years after signature (1983-1986); the Nairobi Convention required eleven years (1985-1996); the Tehran Convention 2003 for the Caspian Sea entered into force in 2006, three years after adoption. The Antigua Convention’s two-decade preparatory limbo stands as the longest ratification lag in the UNEP Regional Seas family.

The absence of entry into force is not simply a procedural delay. It means that the Northeast Pacific coastal states lack an operational binding regional-seas instrument for coordinated environmental protection of their shared Pacific marine environment. The practical consequences include:

No binding obligation to cooperate on marine pollution emergency response beyond what each state undertakes unilaterally or through bilateral arrangements.
No regional Protocol establishing minimum standards for land-based sources of pollution, forcing each state to rely on its national legislation alone.
No regional specially protected areas list that would coordinate MPA management across the seven prospective Parties.
No formal COP structure to which the Secretariat reports and from which it receives binding guidance.
No trust fund with formal assessed contributions, limiting the financial sustainability of the preparatory process.
No mechanism for compulsory dispute settlement under the Convention framework, leaving any inter-Party marine-environment disputes to be addressed through UNCLOS Part XV or bilateral diplomatic channels.

The principal causes of slow progress toward entry into force mirror those identified in academic literature on Central American environmental governance:

Domestic legislative congestion: in several prospective Parties the Convention text has sat in legislative pipelines for years behind higher-priority instruments (trade agreements, security treaties, debt arrangements) without active opposition but without active prioritization either. Marine environmental treaties do not generate the domestic political salience of, for example, bilateral investment or security agreements.

Limited domestic marine environmental constituency: in the Northern Triangle Parties (Guatemala, El Salvador, Honduras), marine environmental issues had relatively low domestic political salience through the 2000s and 2010s, with terrestrial deforestation, mining, and watershed protection drawing more attention and NGO pressure. Coastal fishing communities, the natural domestic constituency for Convention ratification, are not organized at the scale needed to push legislation through congested parliamentary calendars.

Capacity constraints on compliance assessment: ratifying ministries must assess national administrative capacity to implement Convention obligations before depositing instruments of ratification. In several prospective Parties this assessment has been complicated by overlapping national and sub-national environmental authority structures, unclear institutional mandates between fisheries, environment, and maritime affairs ministries, and a shortage of trained marine environmental lawyers capable of mapping Convention obligations to national legislation.

Absence of triggering incidents: no major regional pollution incident comparable to the tanker spills that accelerated ratification of conventions in other regions has occurred in the Antigua Convention area since 2002. The absence of a visible crisis removes the strongest political lever for accelerating ratification.

Eastern Tropical Pacific Marine Corridor (CMAR, 2004)

The Eastern Tropical Pacific Marine Corridor (Corredor Marino del Pacifico Este Tropical, CMAR) is a regional cooperation initiative established by Costa Rica, Panama, Colombia and Ecuador through the San Jose Declaration of 2 April 2004. CMAR is not a Protocol under the Antigua Convention and does not depend on the Convention’s entry into force. It spans both the Antigua Convention area (Costa Rica and Panama Pacific waters) and the Lima Convention area (Colombia and Ecuador Pacific waters). It is a separate intergovernmental initiative that operates in parallel with both Conventions.

CMAR covers a marine corridor connecting four major offshore island marine protected areas of the Eastern Tropical Pacific:

Cocos Island (Costa Rica) at 5.5 degrees N, 87 degrees W, a UNESCO World Heritage Site (1997) covering 18,950 km squared of EEZ MPA after the 2021 Bicentennial Marine Management Area expansion.
Coiba Island (Panama) at 7.5 degrees N, 81.7 degrees W, a UNESCO World Heritage Site (2005) covering approximately 270,000 hectares of marine and terrestrial protected area in the Gulf of Chiriqui.
Malpelo Sanctuary (Colombia) at 4 degrees N, 81.6 degrees W, a UNESCO World Heritage Site (2006) covering approximately 8,575 km squared of remote oceanic reef habitat.
Galapagos Marine Reserve (Ecuador) at approximately 1 degree S, 91 degrees W, the largest of the four sites at approximately 198,000 km squared (after the 2022 Hermandad expansion) and the only IMO PSSA in the broader region.

The CMAR initiative was launched at the 5th IUCN World Parks Congress in Durban, South Africa in September 2003 and formalized through the San Jose Declaration of 2 April 2004. The four Parties committed to coordinate scientific research across the four MPAs, share monitoring data on migratory species (hammerhead sharks, sea turtles, humpback whales), coordinate enforcement against IUU fishing in the corridor waters, harmonize tourism management to reduce visitor pressure on the islands, and pursue joint funding from international donors for corridor-scale conservation. CMAR has been operationalized through a small CMAR Coordination Office and through annual ministerial meetings. The initiative is one of the few functioning regional MPA networks globally and is widely cited as a model for ocean-basin MPA cooperation independent of a binding regional-seas framework.

Cocos Island 18,950 km squared Costa Rican EEZ MPA

Cocos Island (Isla del Coco) is the largest and most biologically distinguished marine protected area within the Antigua Convention region. Cocos is an uninhabited island of approximately 24 km squared located at 5.5 degrees N, 87 degrees W, approximately 550 km southwest of the Costa Rican mainland, the only emergent oceanic island in the Eastern Tropical Pacific outside the Galapagos. The island and its surrounding waters constitute the Parque Nacional Isla del Coco, a Costa Rican protected area established in 1978 and progressively expanded through 1991, 2001, 2017 and most consequentially in 2021 with the establishment of the Bicentennial Marine Management Area (Area Marina de Manejo Bicentenario) which brought the total managed area to approximately 18,950 km squared.

The 2021 expansion was announced by President Carlos Alvarado on the occasion of the bicentennial of Costa Rican independence (1821-2021) and represented a quintupling of the previously protected area. The Bicentennial expansion was the largest single MPA designation in Latin America in 2021 and brought Costa Rica’s marine protected estate from approximately 2.7 percent of EEZ to approximately 30 percent of EEZ, meeting the Kunming-Montreal Global Biodiversity Framework 30x30 target twelve years ahead of schedule.

Cocos Island is internationally significant for several reasons:

UNESCO World Heritage Site: inscribed in 1997 and extended in 2002 for its outstanding universal value as a tropical wet forest island and for its marine biodiversity.
Hammerhead shark aggregations: the Alcyone seamount north of Cocos hosts seasonal aggregations of hundreds to thousands of scalloped hammerhead sharks (Sphyrna lewini), one of the largest known aggregations of this critically endangered species.
Endemic species: Cocos hosts at least 70 endemic plant species, three endemic bird species (Cocos finch, Cocos flycatcher, Cocos cuckoo), several endemic reptiles and a distinctive marine community.
Hydrothermal seamounts: the seafloor around Cocos includes seamount features supporting deep-sea ecosystems with cold-water corals and chemosynthetic communities.
Cinematic heritage: Cocos was the inspiration for Robert Louis Stevenson’s Treasure Island and the location setting for the 1993 film Jurassic Park (location filming was in Hawaii).

The Cocos MPA is a flagship of the Antigua Convention region and a centrepiece of the CMAR Marine Corridor, with the Cocos-Galapagos seamount chain forming a continuous biological corridor connecting Costa Rican and Ecuadorian waters across the Lima-Antigua Convention boundary.

Cocos-Galapagos seamounts and the UN High Seas Treaty

The marine corridor between Cocos Island (Costa Rica) and the Galapagos archipelago (Ecuador) lies partly in the EEZs of Costa Rica and Ecuador and partly in the high seas (areas beyond national jurisdiction, ABNJ) between the two EEZs. This high-seas pocket includes the Cocos Ridge and a series of seamounts that act as biological stepping stones for migratory species transiting between the Cocos and Galapagos hotspots.

The high-seas component of the Cocos-Galapagos corridor has historically lacked a binding regional management framework. The Lima Convention covers Ecuadorian waters but not the high-seas pocket; the Antigua Convention covers Costa Rican waters but also not the high-seas pocket; and no regional MPA network in 2026 binds states to manage the high-seas portion. The South Pacific Regional Fisheries Management Organisation (SPRFMO) has authority over high-seas fisheries in the region but its mandate is narrower than full ecosystem management.

The 2023 BBNJ Agreement (Agreement under UNCLOS on the Conservation and Sustainable Use of Marine Biological Diversity of Areas Beyond National Jurisdiction), commonly called the High Seas Treaty, opened a pathway for binding high-seas MPA designation in the Cocos-Galapagos corridor. The BBNJ Agreement was adopted by the UN General Assembly in June 2023 and opened for signature in September 2023 at the UN headquarters in New York. The Agreement requires 60 ratifications to enter into force.

Costa Rica and Ecuador have led a multi-state coalition to designate the Cocos-Galapagos high-seas corridor as one of the first BBNJ MPAs upon the Treaty’s entry into force, with an estimated area of approximately 300,000 km squared of high-seas waters between the EEZs. The coalition includes Panama and Colombia (CMAR partners), El Salvador, the European Union, Canada and the United Kingdom as supporting states. The BBNJ MPA proposal is intended for submission to the BBNJ Conference of the Parties once entry into force is achieved.

The Cocos-Galapagos BBNJ initiative is strategically important for the Antigua Convention region: it would close the regulatory gap between the EEZs of Costa Rica and Ecuador, give the CMAR Marine Corridor a continuous protected-area envelope, and establish a template for high-seas MPA designation in other UNEP regional-seas regions.

Panama Canal Pacific approach in convention waters

The Panama Canal, opened on 15 August 1914 and operated since the 1999 transfer by the Autoridad del Canal de Panama (ACP), connects the Pacific to the Caribbean across the 80 km wide Isthmus of Panama. The Pacific approach to the Canal is wholly within the Antigua Convention area: the Bay of Panama, the Pacific channel from the Bay to the Miraflores Locks, the Balboa terminal, the Punta Mala light at the southwestern entrance to the Bay, and the open Pacific approach south of Panama Bay.

The Canal carries approximately 6 percent of global maritime trade by tonnage and approximately 14,000 transits per year (2024 figure) of commercial vessels including bulk carriers, container ships, LNG carriers, vehicle carriers, tankers and cruise ships. The 2016 Canal expansion (the Third Set of Locks project) opened the Canal to Neopanamax vessels of up to approximately 366 m length, 49 m beam and 15.2 m draft, more than tripling the cargo-carrying capacity of the Canal.

The Pacific approach traffic is therefore the densest concentration of large-vessel traffic in the Antigua Convention area, with cumulative annual passenger and cargo movements exceeding any other Pacific port complex in the region. The principal pollution and management concerns are:

Oil spill risk: tankers and bunkers transiting the Canal in normal commercial service create persistent low-probability spill risk in the Pacific approach.
Ballast water management: vessels transiting between Pacific and Caribbean ocean basins are major potential vectors for invasive species between the two oceans, with the Canal acting as a freshwater interruption that does not fully neutralize translocation. The Ballast Water Management Convention D-2 standard applies to all Canal-transiting vessels in deep-sea trade.
Anchorage area emissions: vessels waiting for Canal slot allocation anchor in the Bay of Panama, sometimes for several days, with associated air emissions and bunker discharge risks.
Canal-water freshwater discharge: each Canal transit discharges approximately 200 million litres of freshwater from the Gatun Lake to the oceans through the lockage system, redistributing freshwater between the two oceans and altering local salinity at the Pacific and Caribbean approaches.
Bunker fuel sulphur compliance: under the IMO 2020 sulphur cap, all Canal-transiting vessels must use 0.50 percent S fuel or equivalent, with the Pacific approach not being a MARPOL Emission Control Area (the North American ECA does not extend to the Antigua Convention area).

The ACP cooperates with the preparatory process through Panama’s status as a prospective Contracting Party. The future Oil Spills and Emergency Cooperation Protocol, once adopted after Convention entry into force, is expected to designate the Canal Pacific approach as one of the priority zones for regional contingency planning.

Acajutla, Quetzal, Balboa, Corinto and the port network

The major commercial ports of the Antigua Convention area, in approximate north-to-south order:

Puerto Quetzal (Guatemala) at 13.92 degrees N, 90.78 degrees W is the largest Guatemalan Pacific port, handling approximately 0.4 to 0.5 million TEU per year plus bulk cargoes (sugar, coffee, fuel), with a tourism cruise component.

Acajutla (El Salvador) at 13.59 degrees N, 89.83 degrees W is the principal Salvadoran Pacific port, handling around 0.2 to 0.3 million TEU per year plus bulk cargoes and serving as the petroleum import terminal for El Salvador.

San Lorenzo and Henecan (Honduras) on the Gulf of Fonseca are smaller ports serving the limited Honduran Pacific coast with bulk and break-bulk cargoes.

Corinto (Nicaragua) at 12.48 degrees N, 87.18 degrees W is the principal Nicaraguan Pacific port, handling around 0.05 to 0.1 million TEU per year plus bulk cargoes including sugar exports.

Caldera (Costa Rica) at 9.92 degrees N, 84.72 degrees W in the Gulf of Nicoya is the principal Costa Rican Pacific port, handling around 0.3 to 0.4 million TEU per year. Costa Rica’s Caribbean port complex (Puerto Limon-Moin) is materially larger and is the primary Costa Rican container gateway, but Limon-Moin is in the Cartagena Convention area, not the Antigua Convention area.

Balboa (Panama) at 8.96 degrees N, 79.55 degrees W is the Pacific terminal of the Panama Canal, with container terminals operated by Panama Ports Company (Hutchison) and serving as a major transhipment hub for Pacific-Caribbean and intra-Pacific cargo. Balboa handles approximately 3 to 4 million TEU per year and is one of the largest container ports in Latin America.

Buenaventura (Colombia) at 3.88 degrees N, 77.05 degrees W is Colombia’s principal Pacific port, handling approximately 1.5 to 2 million TEU per year, and the main gateway for Colombian Pacific trade with East Asia. Buenaventura sits on the northern reach of the Lima Convention area/southern reach of the Antigua Convention area and is relevant to both regimes in terms of its pollution management obligations.

The port complexes are the principal sources of land-based and ship-source pollution loading to the Convention area and are priority sites for the future Oil Spills Protocol implementation.

Colombia and its dual Lima-Antigua Pacific position

Colombia is the sole state in the prospective Antigua Convention membership that is also a Party to the Lima Convention 1981 and to the Cartagena Convention 1983, giving it the most complex regional-seas treaty portfolio of any state in the Americas. Colombia’s Pacific coast runs from the Panama border south through the Darien and Choco regions to the Narino department boundary with Ecuador, with the major port at Buenaventura and significant offshore island features including the Malpelo Sanctuary.

Colombia’s Pacific coast is split between two UNEP Regional Seas areas: the northern sector falls under the Antigua Convention (where Colombia is a prospective Party), while the southern sector toward the Ecuadorian border falls under the Lima Convention (where Colombia is a Contracting Party with five Protocols in force). The boundary between the two areas corresponds approximately to Colombia’s EEZ boundary with Panama.

The Malpelo Sanctuary at approximately 4 degrees N, 81.6 degrees W is Colombia’s most internationally significant marine protected area in the Pacific, a UNESCO World Heritage Site (2006) covering approximately 8,575 km squared of oceanic reef habitat. Malpelo sits in the CMAR Marine Corridor between Cocos (Costa Rica) and Galapagos (Ecuador) and is a node in the Cocos-Galapagos seamount chain. Because Colombia is a CMAR partner, Malpelo is operationally integrated into the CMAR framework regardless of the Antigua Convention’s non-entry-into-force status.

Colombia’s administrative capacity in the UNEP Regional Seas framework is stronger than that of the Northern Triangle states but complicated by the internal security and development challenges of the Colombian Pacific coast, which is one of the least administratively integrated regions of the country. The Colombian Ministry of Environment and Sustainable Development (Minambiente) and the General Maritime Directorate (DIMAR) are the national authorities with jurisdiction over the relevant treaty obligations. Colombia’s Pacific coast is also the site of some of the most documented biodiversity on Earth per unit area (the Choco bioregion), giving the Convention area a conservation profile that strengthens the case for the SPA Protocol once the parent Convention enters into force.

Colombia’s dual Lima-Antigua position means it operates simultaneously as a Contracting Party with binding Lima obligations for its southern Pacific coast and as a prospective Party with no binding Antigua obligations for its northern Pacific coast. The dividing line between the two jurisdictional zones falls along the Colombia-Ecuador EEZ boundary, not along any ecological or hydrographic feature, creating a governance discontinuity along a continuous biological ecosystem. The CMAR initiative partially bridges this discontinuity through voluntary cooperation across the Malpelo-Coiba-Cocos-Galapagos chain, but CMAR cannot substitute for binding treaty obligations.

IUU fishing: yellowfin tuna, dorado and the IATTC framework

The Northeast Pacific is one of the principal global hotspots for illegal, unreported and unregulated (IUU) fishing by both regional national fleets and distant-water fleets. The principal target species are:

Yellowfin tuna (Thunnus albacares): the dominant tuna species of the Eastern Tropical Pacific, harvested by purse seine, longline and pole-and-line fisheries. The eastern Pacific yellowfin stock is managed by the Inter-American Tropical Tuna Commission (IATTC) based in La Jolla, California, with annual quotas allocated to member states and to distant-water fleet members. IUU yellowfin landings in Central American ports are estimated at 5 to 15 percent of total reported landings, with under-reporting of catch from high-seas international waters and from EEZ incursions.
Bigeye tuna (Thunnus obesus): the second major tuna species, with distinct stock structure and IATTC management. Bigeye is the principal target of the longline fishery.
Skipjack tuna (Katsuwonus pelamis): the smallest of the major tunas by individual size and the dominant species in the Eastern Pacific purse seine fishery, with stocks generally healthy but with concerns about juvenile bycatch.
Dorado (Coryphaena hippurus), also called mahi-mahi or dolphinfish: a fast-growing pelagic species harvested by longline and recreational fisheries throughout the region. Dorado is a major commercial species in Costa Rica, Panama, Ecuador and Peru, with regional landings of around 50,000 to 100,000 tonnes per year. Dorado stock assessment is complicated by the species’ fast life history (typically 1-3 year lifespan) and there are recurring concerns about overfishing in some sub-areas.
Swordfish (Xiphias gladius): a longline-targeted billfish species with distinct Eastern Pacific stock managed by IATTC.
Sharks: scalloped hammerhead, silky shark, oceanic whitetip, blue shark and others, harvested both as target and bycatch by longline and gillnet fisheries. Shark IUU fishing is a particular concern given the conservation status of several species (CITES Appendix II for hammerhead since 2013, oceanic whitetip and silky shark since 2017) and the persistent shark-finning practice.

The Antigua Convention preparatory process supports IUU fishing dialogue through the proposed Specially Protected Areas Protocol (which would establish the regional MPA list with cooperative enforcement) and through cooperation with IATTC, the International Commission for the Conservation of Atlantic Tunas (ICCAT) for some boundary stocks, and the Port State Measures Agreement (PSMA) which all seven prospective Antigua Parties have ratified or are in process of ratifying. The principal IUU enforcement gap in 2026 is the absence of an Antigua-specific Protocol obligation comparable to the Lima Paipa Protocol, leaving the regional framework dependent on the IATTC and PSMA instruments.

Mangrove deforestation along the Convention area

Mangrove ecosystems along the Pacific coast of Central America and northwestern South America have undergone severe historical losses. The aggregate mangrove cover of the prospective Antigua Convention Parties on their Pacific frontages has fallen by approximately 50 percent since 1980 according to successive Global Mangrove Watch assessments and the FAO Mangrove Forests of the World reports, which document Pacific Central American mangrove cover declining from approximately 350,000 hectares in 1980 to approximately 175,000 hectares in 2020. National-level figures vary, with El Salvador and Nicaragua experiencing higher proportional losses (60-70 percent locally) and Costa Rica and Panama experiencing lower losses (30-40 percent).

The drivers of mangrove loss in the region are well-documented:

Shrimp aquaculture: the Penaeus vannamei (whiteleg shrimp) and Penaeus stylirostris aquaculture industry expanded rapidly through the 1980s and 1990s along the Pacific coasts of Guatemala, El Salvador, Honduras, Nicaragua and Colombia. Pond construction typically required mangrove clearance, with cumulative mangrove area lost to shrimp farms estimated at 40 to 60 percent of original cover in the most affected estuaries.
Salt extraction: traditional salt-pan operations along the Salvadoran and Honduran Pacific coasts have cleared substantial mangrove area, though at lower aggregate scale than shrimp aquaculture.
Urban development: the major coastal cities (Acajutla, Corinto, Puntarenas, Panama City, Buenaventura) have expanded into adjacent mangrove zones over the past half-century.
Tourism infrastructure: hotel, marina and resort development along the Costa Rican (Guanacaste, Quepos) and Panamanian (Bocas, Pearl Islands) Pacific coasts has consumed coastal mangrove area.
Charcoal and fuelwood extraction: in lower-income jurisdictions (Honduras, Nicaragua) traditional fuelwood harvest has degraded mangrove stand quality without necessarily clearing entire stands.

The mangrove loss has cascading consequences: loss of nursery habitat for fish and shellfish (with downstream consequences for inshore fisheries), loss of coastal protection against storm surge (with consequences for coastal community vulnerability to tropical storms), loss of carbon sequestration capacity (mangroves are among the most carbon-dense ecosystems on Earth, with estimated carbon storage of 1,000 to 2,000 tonnes CO2-equivalent per hectare), and loss of biodiversity. The Ramsar Convention on Wetlands designates several mangrove sites along the Antigua Convention area: Bahia de Jiquilisco (El Salvador, 63,000 ha), Estero Real (Nicaragua, 81,000 ha), Tempisque-Terraba-Sierpe (Costa Rica, 70,000 ha cumulative across multiple Ramsar sites) and David Estuary (Panama). Ramsar designation provides international visibility but limited binding protection, and the future Antigua Specially Protected Areas Protocol would substantially strengthen the regional framework once adopted.

Tourism pressure: Costa Rica, Panama, Colombian Pacific

The Pacific coast of the Antigua Convention area hosts internationally significant tourism destinations that exert substantial pressure on coastal and marine ecosystems:

Costa Rican Pacific North (Guanacaste): from the Papagayo Peninsula through Tamarindo, Nosara and Samara, the Costa Rican Guanacaste coast receives approximately 1.5 to 2 million international tourists per year, with concentrated hotel infrastructure and a rapidly growing cruise port at Puerto Caldera and the Liberia airport-adjacent resort developments. Costa Rica has implemented stronger coastal-zone management than its regional peers but tourism pressure is the principal pressure on the Pacific North coast.
Costa Rican Pacific Central and South: from Puntarenas through Quepos-Manuel Antonio to the Osa Peninsula, the central Pacific coast hosts nature-tourism destinations focused on national park access (Manuel Antonio, Corcovado, Marino Ballena).
Panamanian Pacific (Bocas Chiriqui, Pearl Islands, Coiba): the Panamanian Pacific tourism market has significant high-end ecotourism components at the Pearl Islands archipelago and around Coiba National Park.
Colombian Pacific (Tumaco, Nuqui, Bahia Solano): the Colombian Pacific coast has a smaller but growing ecotourism sector, with whale-watching in the Bahia Malaga and Uramba Bahia Malaga National Natural Park as a standout seasonal draw. Humpback whales aggregate in Bahia Malaga from July to November and the site receives approximately 5,000 to 10,000 whale-watching visitors per year.
Cruise ship traffic: the major Pacific cruise ports include Puerto Quetzal (Guatemala), Puerto Caldera (Costa Rica) and Balboa (Panama, as transit terminal for Panama Canal cruises). Aggregate cruise calls in the Antigua Convention area are approximately 1,500 to 2,000 calls per year, with associated bunker emissions, sewage discharge and grey-water discharge pressures regulated under MARPOL Convention Annexes IV and V.

Plastic pollution: regional hot spots

Plastic pollution along the Pacific coast of Central America and northwestern South America is concentrated at several principal nodes:

San Salvador-Acajutla corridor (El Salvador): the Lempa River discharge and the Acajutla industrial port complex constitute one of the most concentrated plastic-pollution hotspots in Central America.
Managua-Corinto corridor (Nicaragua): the parallel Rio Estero Real corridor delivers plastic from the Nicaraguan interior to the Pacific Estero Real estuary.
Costa Rican Central Pacific: the Tarcoles River discharge, draining the Greater Metropolitan Area of San Jose (population around 2.5 million), is one of the most plastic-polluted rivers in Latin America by per-capita and per-area discharge metrics. Costa Rica has implemented progressive plastic regulation (single-use plastic bans) but the legacy plastic load in the Tarcoles and Grande de Terraba systems remains significant.
Panama City coastal zone: the Bay of Panama receives concentrated urban plastic input from the Panama City metropolitan area (population around 2 million), with the dynamic tidal regime of the Bay (3 to 5 metre semi-diurnal range) distributing plastic widely across the coastal zone.
Colombian Choco coast: the Pacific coastal zone of Colombia’s Choco department, one of the rainiest regions on Earth (annual precipitation exceeding 8,000 mm in parts), experiences high riverine plastic delivery from the San Juan de Micay and Baudo watersheds.

The aggregate plastic pollution pressure on the Antigua Convention area is one of the principal concerns of the proposed Land-Based Sources Protocol and is the subject of regional cooperation under the UN Environment Programme Clean Seas Campaign and the prospective Global Plastics Treaty under negotiation through the UN Intergovernmental Negotiating Committee (INC) since 2022.

Climate vulnerability: Pacific tropical storms and warming

The Pacific coast of Central America is increasingly exposed to tropical storm and hurricane activity as ocean temperatures in the Eastern Pacific warm under climate forcing. Historically, the Eastern Pacific hurricane basin has been one of the more active tropical-cyclone basins globally, but most Eastern Pacific hurricanes recurve westward into the open Pacific without making landfall. Several high-impact events in recent decades have focused attention on the intensifying risk:

Hurricane Manuel (2013): a Category 1 hurricane that made landfall in the Jalisco and Guerrero coast causing severe flooding and over 120 deaths, with the Manzanillo-Lazaro Cardenas corridor particularly affected.
Hurricane Patricia (2015): the strongest Eastern Pacific hurricane on record by maximum sustained winds (215 mph at peak), making landfall in Jalisco, Mexico at Category 4 intensity with relatively limited human impact due to a sparsely populated landfall location.
Hurricane Otis (2023): a Category 5 hurricane that intensified from Category 1 to Category 5 in less than 24 hours before landfall in Acapulco, devastating the Acapulco metropolitan area with over 50 deaths and economic losses estimated at over US$15 billion. Otis was widely discussed as a climate-change-attributable rapid intensification event.
Tropical Storm Pilar (2023): caused severe flooding along the Pacific coast of El Salvador, Nicaragua and Honduras.

The combination of warming sea-surface temperatures, increased atmospheric moisture, and locked-in coastal infrastructure exposure means that climate vulnerability of the Antigua Convention area is increasing on a multi-decadal trajectory. The Convention preparatory work programme has identified climate adaptation and disaster risk reduction as priority areas for the proposed Oil Spills and Emergency Cooperation Protocol, which would extend beyond pure pollution emergencies to include climate-driven storm-event response coordination.

Differential MARPOL implementation (Pacific side weaker than Caribbean)

A persistent structural feature of the Antigua Convention area is the two-tier MARPOL implementation within the six dual-coast prospective Parties (Guatemala, Honduras, Nicaragua, Costa Rica, Panama) and Colombia. On the Caribbean side these Parties operate under:

the Wider Caribbean MARPOL Annex V Special Area (designated 1991, in effect from 4 May 1993), with stricter garbage discharge rules;
the Cartagena Convention 1983 with its three in-force Protocols (Oil Spills 1983, SPAW 1990, LBS 1999);
the UNEP-CEP regional contingency plan with the Regional Activity Centre at Curacao (RAC-REMPEITC-Carib) providing operational coordination;
a denser network of regional cooperation through the Caribbean Community (CARICOM), the Central American Integration System (SICA), and the Wider Caribbean Region UN agencies.

On the Pacific side the same Parties operate under:

the Antigua Convention not yet in force, with no adopted Protocols;
the global MARPOL Annexes I-VI without any Special Area or PSSA designation in the Pacific Convention area;
no regional Activity Centre comparable to RAC-REMPEITC-Carib;
weaker regional cooperation networks than on the Caribbean side.

The practical consequence is that port-State control intensity, flag-State implementation of MARPOL, emergency response capacity and contingency-plan exercising are systematically weaker on the Pacific side of the same Parties. In Costa Rica, for example, the MARPOL inspection regime at Caribbean ports (Limon-Moin) has historically operated at higher intensity than at Pacific ports (Caldera, Puntarenas), reflecting both the higher vessel traffic on the Caribbean side and the stronger regional cooperation framework. Similar patterns are documented in Panama (Cristobal vs Balboa), Honduras (Puerto Cortes vs San Lorenzo), Nicaragua (Bluefields vs Corinto).

The closure of this two-tier gap is one of the central rationales for the Antigua Convention’s entry into force and the rapid adoption of Oil Spills and LBS Protocols, which would bring the Pacific side of the dual-coast Parties up to broad parity with the Caribbean side.

Absence of MARPOL Special Areas and PSSAs in convention area

The Antigua Convention area contains zero MARPOL Special Areas under any of the six MARPOL Annexes and zero IMO Particularly Sensitive Sea Areas (PSSAs) as of 2026. This is a notable regulatory gap given the ecological significance of the Eastern Tropical Pacific.

The contrast with adjacent regional seas is sharp:

The Wider Caribbean (Cartagena Convention area) has the MARPOL Annex V Special Area designated 1991/1993.
The South-East Pacific (Lima Convention area) has the Galapagos PSSA designated 2005 by MEPC.135(53), with an expansion proposal under MEPC review since 2024.
The Mediterranean (Barcelona Convention area) has multiple MARPOL Special Areas (Annexes I, V) and the PSSA Strait of Bonifacio plus the PSSA Western European Waters at the Atlantic boundary.
The Baltic (HELCOM area) is a MARPOL Special Area for Annexes I, II, IV and V plus a SECA and NECA, and contains the Baltic Sea PSSA.

The absence of any IMO designation in the Antigua Convention area reflects the relative novelty of the preparatory work (active UNEP coordination only from the late 1990s), the absence of an in-force Protocol that would provide a clearer institutional basis for proposing a regional designation, the limited capacity of prospective Parties to develop and prosecute IMO Special Area or PSSA proposals through the MEPC process, and the concentration of global MEPC attention on the higher-profile basins.

A future PSSA proposal for the Cocos Island MPA has been periodically discussed at Costa Rican environmental policy forums, with the 2021 Bicentennial Marine Management Area expansion providing a natural foundation. A future PSSA for Coiba National Park in Panama and for the Malpelo Sanctuary in Colombia has been raised at IUCN-led discussions. Neither has yet been brought to the IMO MEPC as a formal proposal as of 2026.

OAS, Pacific Alliance, CAFTA-DR and SICA coordination

The Antigua Convention preparatory process sits within a wider lattice of regional intergovernmental institutions. The principal complementary frameworks are:

Organization of American States (OAS): a hemispheric political organisation founded 1948, headquartered in Washington DC, with 34 active member states. The OAS Department of Sustainable Development supports environmental cooperation across the hemisphere, and the OAS hosts the Inter-American Commission on Human Rights which has issued environmental-rights jurisprudence relevant to coastal communities. All seven prospective Antigua Parties are OAS members.
Pacific Alliance: an integration bloc founded 2011 by Chile, Colombia, Mexico and Peru, with Costa Rica as candidate member and Panama as observer. The Pacific Alliance has a Pacific Strategy on Marine Spatial Planning and Blue Economy that complements the Antigua Convention preparatory work. Three of the seven prospective Antigua Parties (Colombia, Costa Rica, Panama) have substantive Pacific Alliance engagement.
CAFTA-DR (Central America Free Trade Agreement plus Dominican Republic): a free-trade agreement among Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua, the Dominican Republic and the United States, signed 2004 and progressively in force from 2006. CAFTA-DR includes an Environmental Cooperation Agreement (ECA) with funding for environmental institutional strengthening in the Central American Parties.
Central American Integration System (SICA): a regional integration framework founded 1991. SICA’s Central American Commission on Environment and Development (CCAD) is the regional environmental institution and a natural counterpart to the Antigua Convention preparatory process.
United States and Canada bilateral cooperation: although neither the US nor Canada is a prospective Party to the Antigua Convention, both engage substantively through bilateral assistance (NOAA marine debris programmes in Central America, Canadian DFO scientific cooperation) and through multilateral institutions.

The lattice of regional institutions around the Antigua Convention is dense but uncoordinated, with overlapping mandates and competing meeting calendars. Rationalizing this lattice is a periodic theme of UNEP-CEP regional planning.

Kunming-Montreal GBF 30x30 commitments

The Kunming-Montreal Global Biodiversity Framework, adopted at the 15th Conference of the Parties to the Convention on Biological Diversity (CBD COP-15) in Montreal, December 2022, established the global 30x30 target: protect 30 percent of terrestrial and marine areas by 2030. The 30x30 target has implications for every UNEP regional-seas region and is a structural driver of national MPA expansion among the prospective Antigua Parties.

Among the seven prospective Antigua Parties:

Costa Rica: through the 2021 Bicentennial Marine Management Area expansion, Costa Rica’s MPA estate now exceeds 30 percent of EEZ, meeting the 30x30 target nine years ahead of schedule. Costa Rica is one of the few Latin American jurisdictions with formally certified 30x30 compliance.
Panama: the Coiba National Park, the Pearl Islands MPA and the Cordillera de Coiba MPA designations bring Panama’s marine protection to approximately 30 percent of EEZ, with formal 30x30 compliance achieved in 2023 through the Cordillera de Coiba designation.
Colombia: the Malpelo Sanctuary, the Uramba Bahia Malaga National Natural Park, and additional Pacific MPAs bring Colombia’s Pacific MPA estate to around 15-20 percent of its Pacific EEZ as of 2024, with progress toward 30x30 dependent on additional Pacific designations.
Guatemala, El Salvador, Honduras, Nicaragua: marine protection in the Pacific waters of these Parties is materially below 10 percent as of 2024, with substantial gaps to 30x30 by 2030. The principal challenge is administrative capacity to designate, declare and manage MPAs at the required scale.

The 30x30 commitments interact directly with the proposed Antigua Specially Protected Areas Protocol: a regionally coordinated MPA list under the SPA Protocol could substantially accelerate 30x30 implementation in the lower-capacity Parties through shared methodology, joint monitoring and pooled funding. This is one of the strongest near-term arguments for both ratifying the Convention and adopting the SPA Protocol, with the 2030 target providing a hard external deadline.

Costa Rica’s “Blue Patrimony” initiative

Costa Rica’s Blue Patrimony (Patrimonio Azul) initiative is a national flagship marine conservation programme launched in 2017 and expanded progressively through subsequent administrations. The initiative bundles together:

Cocos Island National Park and the 2021 Bicentennial Marine Management Area expansion;
the Marino Ballena, Manuel Antonio and Cahuita national parks (Cahuita on the Caribbean side);
the Gulf of Nicoya, Tempisque and Terraba-Sierpe Ramsar wetland systems;
the Cocos seamount complex at the boundary with the high seas;
the Sustainable Blue Economy strategy with sectoral targets for fisheries, tourism, shipping and aquaculture;
the proposed BBNJ MPA designation at the Cocos-Galapagos high-seas corridor in cooperation with Ecuador.

Blue Patrimony is widely cited as the most coherent national marine policy framework in Latin America and serves as a regional benchmark for other Antigua Convention prospective Parties. The initiative draws on the Costa Rican environmental tradition (the 1969 Forestry Law, the 1996 Biodiversity Law, the Payments for Ecosystem Services programme since 1997) and applies the same logic to the marine domain.

Costa Rica has framed Blue Patrimony as a contribution to the 30x30 target, the BBNJ Treaty implementation, the Antigua Convention SPA Protocol development and the CMAR Marine Corridor strengthening. The diplomatic visibility of Blue Patrimony, particularly through Costa Rica’s hosting of multiple international ocean conferences (UN Ocean Conference Lisbon 2022 co-host, BBNJ negotiations co-facilitator), has substantially raised the regional profile of the Antigua Convention region in global ocean-governance discussions.

Comparison to Lima Convention 1981 (parallel SE Pacific)

The Lima Convention 1981 is the regional-seas counterpart for the South-East Pacific (Panama, Colombia, Ecuador, Peru, Chile) and the most direct comparator to the Antigua Convention. The two regimes share the same Pacific Ocean basin, divided at the Colombia-Panama maritime boundary at approximately 7 degrees N, with Colombia as a prospective Antigua Party for its northern Pacific coast and a Lima Party for its southern Pacific coast and Panama as a prospective Antigua Party for its broader Pacific frontage.

Key contrasts:

Entry into force: Lima 1986 (5 years after signature); Antigua not yet in force as of 2026 (24 years after adoption).
Prospective Parties: Lima 5 (Chile, Colombia, Ecuador, Panama, Peru); Antigua 7 (Colombia, Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua, Panama).
Coastline: Lima approximately 10,000 km; Antigua approximately 6,500 km.
Protocols in force: Lima 5 (Lima Hydrocarbon, Quito Supplementary Hydrocarbon, Quito LBS, Paipa SPA, Paipa Radioactive); Antigua 0.
Secretariat: Lima permanent at CPPS Guayaquil; Antigua rotating through UNEP-CEP coordination.
PSSA: Lima has Galapagos PSSA (MEPC.135(53) 2005); Antigua has none.
MARPOL Special Areas: neither has any.
Dominant ecosystem: Lima Humboldt Current (cold upwelling, anchoveta-fishmeal); Antigua Eastern Tropical Pacific (warm tropical, tuna-dorado).
Founding intergovernmental body: Lima built on CPPS founded 1952 (Santiago Declaration); Antigua built on rotating UNEP-CEP coordination without a dedicated regional body.

The two regimes are structurally complementary: Lima covers the cold-water southern flank and Antigua covers the warm-water northern flank of the Pacific coast of Latin America, with the CMAR Marine Corridor and the future BBNJ Cocos-Galapagos high-seas MPA as the principal cross-Convention bridges.

Comparison to Cartagena Convention 1983 (parallel Caribbean side)

The Cartagena Convention 1983 is the Caribbean-side counterpart for the same six dual-coast prospective Antigua Parties (Guatemala, Honduras, Nicaragua, Costa Rica, Panama) plus 19 other Wider Caribbean states. The two regimes therefore overlap in six of seven prospective Antigua Parties, making Cartagena the closest institutional cousin of Antigua.

Key contrasts:

Entry into force: Cartagena 1986 (3 years after signature); Antigua not yet in force as of 2026 (24 years after adoption).
Parties: Cartagena 25 in the Wider Caribbean Region; Antigua 7 prospective in the Northeast Pacific.
Protocols in force: Cartagena 3 (Oil Spills 1983, SPAW 1990, LBS 1999); Antigua 0.
Secretariat: Cartagena permanent at UNEP-CEP Kingston; Antigua rotating through UNEP-CEP coordination from Kingston with regional support from San Jose.
MARPOL Special Area: Cartagena has the Wider Caribbean Annex V Special Area since 1993; Antigua has none.
Regional Activity Centre: Cartagena has RAC-REMPEITC-Carib at Curacao for oil spills and RAC SPAW at Guadeloupe for protected areas; Antigua has none.
Ecosystem character: Cartagena Caribbean enclosed sea with coral reefs (Mesoamerican Reef on the same isthmus); Antigua open Pacific margin with seamount-island MPAs (Cocos, Coiba, Malpelo).

The asymmetry in Protocol coverage between the two sides of the same isthmus is the principal motivation for closing the gap on the Pacific side through Antigua Convention entry into force and Protocol adoption. The Cartagena Protocol experience provides ready templates for the Antigua Oil Spills, LBS and SPA Protocols, and the institutional architecture (UNEP-CEP, regional secretariats, trust funds) is partly transferable.

Comparison to Noumea Convention 1986 (parallel South Pacific)

The Noumea Convention (Convention for the Protection of the Natural Resources and Environment of the South Pacific Region), adopted at Noumea, New Caledonia in November 1986 and in force since August 1990, is the UNEP regional-seas Convention for the South Pacific island states (Cook Islands, Federated States of Micronesia, Fiji, Kiribati, Marshall Islands, Nauru, New Zealand, Niue, Palau, Papua New Guinea, Samoa, Solomon Islands, Tonga, Tuvalu, Vanuatu, plus France, Australia and the United States as Parties for their Pacific territories).

Key contrasts with Antigua:

Parties: Noumea has 26 Contracting Parties including non-regional powers (France, Australia, US); Antigua has 7 prospective Parties all of which are coastal states of the Convention area.
Geographical extent: Noumea covers the entire South Pacific region of approximately 30 million km squared with 22 island nations and territories; Antigua covers the much smaller Northeast Pacific margin.
Protocols in force: Noumea has 2 in force (Pollution Prevention Protocol on dumping and emergencies, plus Apia Convention reframing); Antigua has 0 adopted.
Secretariat: Noumea is hosted by the Pacific Community (SPC) and the Pacific Regional Environment Programme (SPREP) at Apia, Samoa; Antigua is coordinated through UNEP-CEP.
Climate vulnerability: both regions face significant climate vulnerability but Noumea includes low-lying atoll states with existential sea-level-rise exposure (Kiribati, Tuvalu, Marshall Islands); Antigua exposure is primarily storm-event driven for most of its coastline.
Entry into force speed: Noumea entered into force in August 1990, less than four years after adoption in November 1986. The contrast with Antigua’s 24-year non-entry-into-force illustrates how the Pacific island-state parties to Noumea, despite their smaller size, moved faster than the Central American and Colombian parties to Antigua.

The Noumea Convention provides another Pacific regional-seas precedent and a contrasting model of multi-party Pacific cooperation that entered into force quickly despite the geographic dispersion of its Parties across more than 30 million km squared. The Noumea example is sometimes invoked by UNEP facilitators pressing the Antigua prospective Parties to accelerate ratification, given that Noumea’s island-state Parties had fewer domestic administrative resources than most Antigua prospective Parties yet reached entry into force within four years.

2030 outlook: entry into force, protocol negotiation, blue economy

The 2026-2030 horizon for the Antigua Convention regime is dominated by several work programme priorities:

Entry into force: the foundational requirement before any other formal mechanism can activate. Whether the requisite ratifications are deposited in this horizon will determine whether the regime transitions from a preparatory process to a functioning Convention.
Adoption of the Oil Spills and Emergency Cooperation Protocol: the most advanced of the three priority Protocols, with draft text circulated since the mid-2010s. Adoption requires Convention entry into force followed by a Conference of Plenipotentiaries for the Protocol.
Adoption of the Land-Based Sources Protocol: modelled on the Cartagena LBS 1999 and the Lima Quito LBS 1983 Protocols, addressing untreated sewage, agricultural runoff, plastic pollution and industrial discharge.
Adoption of the Specially Protected Areas Protocol: modelled on the Cartagena SPAW 1990, supporting Kunming-Montreal 30x30 implementation in the prospective Antigua Parties and providing the regional MPA list.
CMAR Marine Corridor strengthening: continuing operationalization of the four-Party CMAR cooperation framework, with potential expansion to include El Salvador and Honduras and engagement with the Galapagos seamount chain.
BBNJ Cocos-Galapagos high-seas MPA designation: dependent on BBNJ Treaty entry into force, with Antigua-Lima joint MPA proposal targeted for the first or second BBNJ COP after entry into force.
30x30 implementation: scaling up MPA coverage in the lower-capacity prospective Parties (Guatemala, Honduras, El Salvador, Nicaragua) to meet the 2030 target.
Blue Economy strategy: developing regional blue-economy frameworks aligned with Costa Rica’s Blue Patrimony model, the Pacific Alliance Blue Economy strategy and the UN Global Biodiversity Framework.
Climate adaptation and disaster risk reduction: building regional capacity for tropical-storm response in the context of intensifying Pacific hurricane activity (post-Otis 2023).

The 2030 outlook is one of potential substantive expansion of the Antigua Convention regime from its current preparatory-process status into a fully operational UNEP regional-seas Convention, subject to the foundational requirement of entry into force. Whether the political and capacity conditions support delivery on this trajectory remains the principal open question.

Limitations

Several limitations apply to this article.

The entry-into-force status of the Antigua Convention is the most significant practical limitation on reporting. The Convention has not entered into force as of 2026. Any description of the Convention regime’s operation draws on preparatory meetings, UNEP coordination arrangements and voluntary cooperation among prospective Parties rather than on binding Convention structures. Reporting on “Contracting Parties” or “the Secretariat” in the conventional sense is technically premature; the article consistently uses “prospective Parties” and “preparatory coordination” to reflect the actual legal status.

The ratification record for this Convention is not reported with the same granularity available for conventions already in force. The article does not attribute specific ratification deposit dates to individual states beyond what is verifiable through UNEP published sources (the UNEP NEP programme page and the UNEP convention text repository). Readers needing current ratification status should consult the UNEP Regional Seas Programme Northeast Pacific page directly.

Quantitative figures for coastline lengths, port throughputs, mangrove cover, MPA areas and IUU fishing estimates are from the sources cited (CIA World Factbook, Global Mangrove Watch, IATTC reports, UNESCO, MINAE Costa Rica, ACP Panama) and are subject to revision as methodologies improve. The 6,500 km coastline aggregate is the canonical UNEP-NEP regional figure; national-level methodology varies.

Protocol progress is based on UNEP-CEP public reporting as of the article’s lastmod date. Protocol draft texts circulate in expert meetings and are not publicly available in full; progress descriptions reflect what UNEP has publicly reported.

The Antigua Convention does not regulate fisheries management directly; fisheries are administered by IATTC, the Central American Fisheries Organisation (OSPESCA) under SICA for some inshore stocks, and national authorities (INCOPESCA in Costa Rica, ARAP in Panama, AUNAP in Colombia). The Convention’s prospective role on fisheries is limited to the future SPA Protocol once adopted.

The Convention does not apply to warships and government vessels in non-commercial service, although the Convention text commits Parties to ensure that such vessels act consistently with the Convention so far as is reasonable and practicable. The Convention extends to internal waters of Parties only insofar as they have notified the Secretariat, meaning some coastal lagoons and estuaries may not be formally within the Convention area.

The Convention does not extend to the Gulf of California / Sea of Cortez sub-basin or to any other Mexican Pacific waters, because Mexico is not a prospective Party to the Antigua Convention. The Convention does not extend to the Caribbean side of the prospective Parties, which is governed by the Cartagena Convention 1983. The Convention does not extend to the South-East Pacific south of the Colombia-Panama boundary, which is governed by the Lima Convention 1981.

Common confusions about this Convention:

The Antigua Convention covers the Caribbean side of any Central American state: it does not. Caribbean waters are under the Cartagena Convention 1983.
The Antigua Convention has entered into force: it has not as of 2026.
Mexico is a Party or prospective Party to the Antigua Convention: Mexico is not. The prospective Parties are Colombia, Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua, and Panama.
The Convention area includes the Galapagos Islands: the Galapagos are in the Lima Convention area (Ecuadorian waters at approximately 1 degree S).
The Antigua Convention area has a MARPOL Special Area designation: there are none as of 2026.
The Convention has Protocols comparable to the Lima or Cartagena regimes: it has zero adopted Protocols as of 2026.
The Cocos Island MPA has the same IMO status as the Galapagos PSSA: Cocos has Costa Rican national MPA status but no IMO PSSA designation as of 2026, in contrast to the Galapagos which is an IMO PSSA under MEPC.135(53) of 2005.

Frequently asked questions

Has the Antigua Convention 2002 entered into force?

No. As of 2026 the Antigua Convention has not entered into force. It was adopted on 18 February 2002 at Antigua, Guatemala and opened for signature, but has not yet obtained the number of ratifications required to trigger entry into force under Article 31 of the Convention.

What states signed or may accede to the Antigua Convention?

The Convention was negotiated by and opened for signature to the coastal states of the Northeast Pacific: Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua, Panama, and Colombia. These seven states form the prospective Contracting Parties to the Convention.

Does the Antigua Convention have any protocols in force?

No. Because the Convention itself has not yet entered into force, no implementing protocols have been adopted. Three protocol themes (oil spills and emergency cooperation, land-based sources of pollution, and specially protected areas) are under expert-group development.

How does the Antigua Convention differ from the Lima Convention?

The Lima Convention 1981 covers the South-East Pacific (Panama, Colombia, Ecuador, Peru, Chile) and has been in force since 1986, with five in-force protocols. The Antigua Convention covers the Northeast Pacific (Colombia to Guatemala, El Salvador, Honduras, Nicaragua, Costa Rica) and is not yet in force as of 2026, with no protocols adopted.

Is the Panama Canal within the Antigua Convention area?

Yes. The Pacific approach to the Panama Canal, including the Bay of Panama, the Pacific channel, the Miraflores Locks approach, and the Balboa terminal, lies within the Convention area. Panama is one of the seven prospective Contracting Parties.