Voracious comb jellyfish 'invisible' to prey

Oct 12, 2010
The North American comb jellyfish Mnemiopsis leidyi has a simple structure with two large oral lobes for catching prey. Credit: Lars Johan Hansson

Despite its primitive structure, the North American comb jellyfish can sneak up on its prey like a high-tech stealth submarine, making it a successful predator. Researchers, including one from the University of Gothenburg, have now been able to show how the jellyfish makes itself hydrodynamically 'invisible'.

The North American comb Mnemiopsis leidyi has long been known to consume vast quantities of zooplankton. A few years ago the species became established in Northern Europe.

Like many other jellyfish, Mnemiopsis leidyi has a large gelatinous body. The large size increases its chances of encountering prey, but can also be a disadvantage since the prey organisms are often highly sensitive to movements in the water. Nevertheless, the comb jellyfish manages to catch large amounts of copepod plankton, which are known for their acute escape response.

'Copepods have a well developed ability to detect even the slightest water disturbance,' says Lars Johan Hansson, a researcher at the Department of at the University of Gothenburg. 'They can swim well clear of the source of water deformation in just a split second. How the comb jellyfish is able to approach and catch some of the animal world's most vigilant plankton has up until now been unknown.'

The researchers used advanced video technology to study water flows around and within the comb jellyfish. These measurements were then used to calculate the water deformation generated by the jellyfish and compare this with the levels that trigger an escape response in .

'It emerged that the comb jellyfish uses microscopic, hairlike cilia inside its oral lobes to generate a feeding current that carefully transports water between the lobes. As the water accelerates slowly and is transported undisturbed into the jellyfish together with the prey, there is nothing that alarms the prey until it is next to the capture site inside the lobes, by which time it's too late to escape. This makes the jellyfish a hydrodynamically silent predator.'

Explore further: Male monkey filmed caring for dying mate (w/ Video)

More information: The study – Stealth predation and the predatory success of the invasive ctenophore Mnemiopsis leidyi – has been published in the scientific journal PNAS.

add to favorites email to friend print save as pdf

Related Stories

New parasite could be late summer beach pest

Jun 09, 2010

Researchers at the University of Gothenburg have discovered a new sea anemone that is thought to have established itself in Swedish waters. Larvae from similar anemones causes skin problems for sea bathers ...

Dutch zoo breeds own jellyfish

Sep 29, 2007

Marine biologists at a Dutch zoo say they have succeeded in the difficult task of breeding jellyfish in captivity.

Australian jellyfish range grows larger

Aug 20, 2007

U.S. marine scientists have discovered the range of the Australian spotted jellyfish (Phylllorhiza punctata) now extends from Texas to North Carolina.

Red Sea coral seen to feed on jellyfish

Nov 17, 2009

(PhysOrg.com) -- Corals depends on the products of photosynthetic algae for most of their food, but they also eat tiny plankton. Now, for the first time, there is evidence of a coral eating jellyfish.

Recommended for you

Male monkey filmed caring for dying mate (w/ Video)

9 hours ago

(Phys.org) —The incident was captured by Dr Bruna Bezerra and colleagues in the Atlantic Forest in the Northeast of Brazil.  Dr Bezerra is a Research Associate at the University of Bristol and a Professor ...

Orchid named after UC Riverside researcher

Apr 17, 2014

One day about eight years ago, Katia Silvera, a postdoctoral scholar at the University of California, Riverside, and her father were on a field trip in a mountainous area in central Panama when they stumbled ...

In sex-reversed cave insects, females have the penises

Apr 17, 2014

Researchers reporting in the Cell Press journal Current Biology on April 17 have discovered little-known cave insects with rather novel sex lives. The Brazilian insects, which represent four distinct but re ...

Fear of the cuckoo mafia

Apr 17, 2014

If a restaurant owner fails to pay the protection money demanded of him, he can expect his premises to be trashed. Warnings like these are seldom required, however, as fear of the consequences is enough to ...

User comments : 0

More news stories

Researchers successfully clone adult human stem cells

(Phys.org) —An international team of researchers, led by Robert Lanza, of Advanced Cell Technology, has announced that they have performed the first successful cloning of adult human skin cells into stem ...

Researchers develop new model of cellular movement

(Phys.org) —Cell movement plays an important role in a host of biological functions from embryonic development to repairing wounded tissue. It also enables cancer cells to break free from their sites of ...

Male monkey filmed caring for dying mate (w/ Video)

(Phys.org) —The incident was captured by Dr Bruna Bezerra and colleagues in the Atlantic Forest in the Northeast of Brazil.  Dr Bezerra is a Research Associate at the University of Bristol and a Professor ...

Plants with dormant seeds give rise to more species

Seeds that sprout as soon as they're planted may be good news for a garden. But wild plants need to be more careful. In the wild, a plant whose seeds sprouted at the first warm spell or rainy day would risk disaster. More ...