Observations of Litter Deposited in the Deep Waters of Isla del Coco National Park, Eastern Tropical Pacific

Abstract

Marine debris is recognized as a major threat to biodiversity and can be found ubiquitously even in remote regions, including deep-sea environments. Isla del Coco National Park is known as one of the best protected areas around the world, a preferred diving destination, and is also renowned for large aggregations of pelagic species that attract illegal commercial fisheries. Despite its pristine reputation, this study demonstrates that anthropogenic debris can affect this remote and well protected area. Images of marine debris were taken using the DeepSee submersible, mainly plastic litter from fishing gear were found between 200 and 350 m depth. A total of 40 items of debris were found in 5.48% of 365 dives, 60% of the items were plastics, and local boat and fishing activities provided most of litter. Our aim with this research is to raise awareness about the potential problem of solid wastes and fishing gear deposited in the deep environments of Isla del Coco National Park and to explore the potential implications for the ecological integrity of this protected area, including ghost fishing and the possible ingestion of pollutants. These results provide useful management information for the area, especially if one considers the constant pressure of illegal fishing and tourism at Isla del Coco National Park.

Microplastics found in the World Heritage Site Cocos Island National Park, Costa Rica

“…It could be predicted that marine lobsters will have a higher exposure to debris than freshwater shrimps. Naranjo-Elizondo and Cortés (2018) found anthropogenic debris at Cocos Island, between 200 and 350 m depth, from which 60% of the items were plastics from local boats and fishing gears. Fishing gears comprised lost lines and most of fishing debris observed in contact with fish or crabs (Naranjo-Elizondo and Cortés 2018).…”

“…Furthermore, Cocos Island is regarded as one of the few effective Marine Protected Areas around the world and it has become famous because of its large aggregations of pelagic species (Naranjo-Elizondo and Cortés 2018). Apart from a few park rangers and some facilities provided for regular visitors such as researchers and volunteers, the island is almost inhabited (Díaz-Bolaños et al 2012).…”

Diversity of Deep-Sea Echinoderms From Costa Rica

“…The shrimp trawling is currently prohibited in Costa Rica (Sala Constitucional, 2013), however, there has been recent and continuous efforts to re-activate this activity. Finally, litter has also been observed in Costa Rican deep-sea waters around Isla del Coco, composed mainly of plastics and lost fishing gear (Naranjo-Elizondo and Cortés, 2018), and in much deeper areas in several locations (J. Cortés per. obs.…”

The low impact of fish traps on the seabed makes it an eco-friendly fishing technique

“…Other issues relating to fish traps could be raised, such as ghost fishing [36] and pollution from traps lost as sea [37,38], but these impacts also exist for other gear types that have higher impacts on the seabed (e.g., gillnets or trammel nets, [39][40][41]; or trawls, [42]). Some solutions have been proposed to mitigate these impacts: the use of natural fibres [43] or biodegradable plastics in some parts of the trap [44] to disarm the gear if it is lost.…”