Crayfish species proves to be the ultimate survivor

Aug 03, 2012
Crayfish
Austropotamobius pallipes. Credit: David Gerke/Wikipedia.

One of the most invasive species on the planet is able to source food from the land as well as its usual food sources in the water, research from Queen Mary, University of London has found.

Scientists analysed the behaviour of red swamp crayfish in Kenya's and found that when the water level of the lake was low, the crayfish found additional on land. The study was published in the journal today.

Lead author Dr Jonathan Grey from Queen Mary, University of London explained: "These crayfish are incredible survivors; our research shows they are able to feed off terrestrial plants directly, as well as – the first study to demonstrate this.

"It has significant implications for anyone looking to introduce these species in other areas."

The research team looked at the diet of the crayfish through a technique called stable isotope analysis, where they used a natural chemical signal of diet in the species' tissues to determine what they were eating.

They found a proportion of the crayfish population had left the main lake and were surviving by burrowing in hippopotamus footprints which left small pools of water. After dark the crayfish clambered out from the footprints and grazed on the surrounding terrestrial plants.

"This study demonstrates how the red swamp crayfish is such an extraordinarily successful invader," Dr Grey said.

The red swamp crayfish has been introduced to multiple locations throughout East Africa from the 1960s to enhance fisheries and to attempt to control populations of snails which carry a parasite causing river blindness in humans.

"While they are useful to counteract other harmful species in ecosystems, they are also extremely damaging to fish populations and the balance of the food web. They eat plants, fish eggs, fly larvae, snails and leeches and since we have now shown that they are able to tap into extra resources from the land, they can sustain higher populations under adverse conditions such as low water and could cause more of a problem in a variety of environments than we initially thought."

Explore further: Rare new species of plant: Stachys caroliniana

Related Stories

Carp dominate crayfish in invasive species battleground

Mar 06, 2012

(PhysOrg.com) -- Louisiana red swamp crayfish and common carp are two of the most invasive species on the planet yet how they interact has only recently been revealed by scientists at Queen Mary, University ...

Hope for Ridding Lakes of Clawed Invader

Jul 31, 2006

The rusty crayfish - a voracious, bullying exotic that has visited ecological havoc on numerous Wisconsin lakes - may have finally met its match.

Recommended for you

Rare new species of plant: Stachys caroliniana

Nov 21, 2014

The exclusive club of explorers who have discovered a rare new species of life isn't restricted to globetrotters traveling to remote locations like the Amazon rainforests, Madagascar or the woodlands of the ...

Mysterious glowworm found in Peruvian rainforest

Nov 21, 2014

(Phys.org) —Wildlife photographer Jeff Cremer has discovered what appears to be a new type of bioluminescent larvae. He told members of the press recently that he was walking near a camp in the Peruvian ...

The unknown crocodiles

Nov 21, 2014

Just a few years ago, crocodilians – crocodiles, alligators and their less-known relatives – were mostly thought of as slow, lazy, and outright stupid animals. You may have thought something like that ...

User comments : 2

Adjust slider to filter visible comments by rank

Display comments: newest first

ormondotvos
4.2 / 5 (5) Aug 03, 2012
But they're a protein source, and no more damaging to the environment than we are... like Asian carp. We should eat them.
Shootist
4 / 5 (4) Aug 03, 2012
We do eat them, at least in Louisiana.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.