Crabs Feel the Pinch | River Scavengers Under Threat
The “vultures” of our river systems are at risk from extinction, reveals new research published today. The IUCN Red List assessment, led by scientists from the Zoological Society of London and Northern Michigan University discovered that about one sixth of all freshwater crab species are threatened with extinction, with habitat loss and pollution to blame.
London, United Kingdom, August 11, 2009 --(PR.com)-- Just like vultures, freshwater crabs play a vital role in the recycling of animal and plant remains that helps maintain the long-term health of tropical aquatic ecosystems. The disappearance of freshwater crabs from these ecosystems would break the nutrient cycle and could seriously affect other animals that feed on them from fish to people.
“The loss of freshwater crabs threatens to interrupt the processes that provide benefits to humans such as nutrient cycling and maintaining water quality” said Dr. Ben Collen from the Zoological Society of London.
He adds: “We must set clear goals to reverse these trends and ensure that our enduring legacy is not to wipe out the small things that provide us with great benefits, such as nutrient cycling and even climate regulation.”
Freshwater crabs are the main catch for small-scale fisheries in many parts of the tropics and often provide the primary source of protein for local people. The decline of these crustaceans could lead to the collapse of local fisheries, and this could have a profound effect on the economy of the villages that depend on them.
“A wide range of predators – such as mongooses, herons, snakes, and catfish - depend on freshwater crabs for their survival, and when the crabs go, these species may follow. For example, we know that the disappearance of crabs from a river ecosystem in Kenya caused the otter population that fed on them to crash,” said freshwater crab biologist, Dr. Neil Cumberlidge of Northern Michigan University.
Freshwater crabs may not be fussy about what they eat, but they are extremely choosy about where they live. The new study showed that the diversity of crab species is highest in tropical rain forests as they have the most favourable habitats and the trees act as natural water filters. Most threatened species of freshwater crabs were shown to be highly sensitive to habitat loss, pollution, and water siltation.
The increasing destruction of rainforests and freshwater ecosystems throughout the tropics means that these crabs need urgent protection.
This study is the first global extinction assessment for any group of freshwater invertebrates. The study provides a valuable source of information for the governments of the 122 countries where these threatened species occur, not least because these nations have pledged to reduce biodiversity loss ahead of the Convention on Biological Diversity meeting next year.
Freshwater crabs and the biodiversity crisis: Importance, threats, status and conservation challenges’ is published today in Biological Conservation.
Editorial Notes
• The IUCN Red List of Threatened Species provides taxonomic, conservation status and distribution information on plants and animals that have been globally evaluated using the IUCN Red List Categories and Criteria. This system is designed to determine the relative risk of extinction, and the main purpose of the IUCN Red List is to catalogue and highlight those plants and animals that are facing a higher risk of global extinction. The IUCN Red List is a joint effort between IUCN, its Species Survival Commission and partners Zoological Society of London, BirdLife International, Conservation International and NatureServe. For further information visitwww.iucnredlist.org
• Founded in 1826, the Zoological Society of London (ZSL) is an international scientific, conservation and educational charity: our key role is the conservation of animals and their habitats. The Society runs ZSL London Zoo and ZSL Whipsnade Zoo, carries out scientific research at the Institute of Zoology and is actively involved in field conservation overseas. For further information please visit www.zsl.org.
• Freshwater crabs are found in 122 countries and primarily inhabit tropical freshwater ecosystems. Most freshwater crabs are omnivorous and include species that feed on leaves, algae, beechnuts, and dead frogs, or snakes. They are the most ecologically important macro-invertebrates in tropical inland waters worldwide. This previously little-known group of brachyurans is now known to be the most species-rich (and possibly the most threatened) group of crabs on Earth.
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“The loss of freshwater crabs threatens to interrupt the processes that provide benefits to humans such as nutrient cycling and maintaining water quality” said Dr. Ben Collen from the Zoological Society of London.
He adds: “We must set clear goals to reverse these trends and ensure that our enduring legacy is not to wipe out the small things that provide us with great benefits, such as nutrient cycling and even climate regulation.”
Freshwater crabs are the main catch for small-scale fisheries in many parts of the tropics and often provide the primary source of protein for local people. The decline of these crustaceans could lead to the collapse of local fisheries, and this could have a profound effect on the economy of the villages that depend on them.
“A wide range of predators – such as mongooses, herons, snakes, and catfish - depend on freshwater crabs for their survival, and when the crabs go, these species may follow. For example, we know that the disappearance of crabs from a river ecosystem in Kenya caused the otter population that fed on them to crash,” said freshwater crab biologist, Dr. Neil Cumberlidge of Northern Michigan University.
Freshwater crabs may not be fussy about what they eat, but they are extremely choosy about where they live. The new study showed that the diversity of crab species is highest in tropical rain forests as they have the most favourable habitats and the trees act as natural water filters. Most threatened species of freshwater crabs were shown to be highly sensitive to habitat loss, pollution, and water siltation.
The increasing destruction of rainforests and freshwater ecosystems throughout the tropics means that these crabs need urgent protection.
This study is the first global extinction assessment for any group of freshwater invertebrates. The study provides a valuable source of information for the governments of the 122 countries where these threatened species occur, not least because these nations have pledged to reduce biodiversity loss ahead of the Convention on Biological Diversity meeting next year.
Freshwater crabs and the biodiversity crisis: Importance, threats, status and conservation challenges’ is published today in Biological Conservation.
Editorial Notes
• The IUCN Red List of Threatened Species provides taxonomic, conservation status and distribution information on plants and animals that have been globally evaluated using the IUCN Red List Categories and Criteria. This system is designed to determine the relative risk of extinction, and the main purpose of the IUCN Red List is to catalogue and highlight those plants and animals that are facing a higher risk of global extinction. The IUCN Red List is a joint effort between IUCN, its Species Survival Commission and partners Zoological Society of London, BirdLife International, Conservation International and NatureServe. For further information visitwww.iucnredlist.org
• Founded in 1826, the Zoological Society of London (ZSL) is an international scientific, conservation and educational charity: our key role is the conservation of animals and their habitats. The Society runs ZSL London Zoo and ZSL Whipsnade Zoo, carries out scientific research at the Institute of Zoology and is actively involved in field conservation overseas. For further information please visit www.zsl.org.
• Freshwater crabs are found in 122 countries and primarily inhabit tropical freshwater ecosystems. Most freshwater crabs are omnivorous and include species that feed on leaves, algae, beechnuts, and dead frogs, or snakes. They are the most ecologically important macro-invertebrates in tropical inland waters worldwide. This previously little-known group of brachyurans is now known to be the most species-rich (and possibly the most threatened) group of crabs on Earth.
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Contact
ZSL London Zoo - Conservation
Victoria Picknell
02074496361
http://www.zsl.org/conservation/
Zoological Society of London
Regent's Park
London
NW1 4RY
Victoria Picknell
02074496361
http://www.zsl.org/conservation/
Zoological Society of London
Regent's Park
London
NW1 4RY
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