Tag Archives: zebra

Die Rekordwanderung der Zebras

WWF entdeckt Afrikas längste Tierwanderung / Satelliten dokumentieren Route über 500 Kilometer zwischen Namibia und Botsuana

Berlin – Forscher haben in Afrika einen bisher unbekannten Rekord aus der Tierwelt aufgespürt: Im Süden des Kontinents wurden viele Hundert Steppenzebras (Equus quagga) bei ihrer 500 Kilometer langen Wanderung zwischen Namibia und Botsuana beobachtet, berichtet der WWF. Kein anderes Säugetier Afrikas lege derart weite Strecken zurück. Entdeckt wurde der Wanderrekord durch eine zweijährige Studie, die der WWF zusammen mit dem namibischen Umwelt- und Tourismusministerium (MET) durchgeführt hat. „Es ist erstaunlich, dass so ein großes und sichtbares Tier anscheinend Jahr für Jahr diese enorme Distanz zurücklegt und wir es so lange nicht bemerkt haben“, so Robin Naidoo, WWF-Mitarbeiter und Leiter der Studie. (more…)

Read More

Limited food may be significantly changing Great Lakes ecosystems

ANN ARBOR — Declines of the food resources that feed lake organisms are likely causing dramatic changes in the Great Lakes, according to a new study.

The study, led by the U.S. Geological Survey and co-authored by three University of Michigan researchers, found that since 1998, water clarity has been increasing in most Great Lakes, while phytoplankton (the microscopic water organisms that feed all other animals), native invertebrates and prey fish have been declining. These food web changes fundamentally affect the ecosystem’s valuable resources and are likely caused by decreasing levels of lake nutrients, and by growing numbers of invasive species such as zebra and quagga mussels. (more…)

Read More

Bad news for prey: New research shows that predators can learn to read camouflage

Camouflaged creatures can perform remarkable disappearing acts but new research shows that predators can learn to read camouflage.

The study, which used human subjects as predators searching for hidden moths in computer games, found that the subjects could learn to find some types of camouflaged prey faster than others. 

The research was carried out by the University of Exeter and the University of Cambridge and is published in the journal PLOS ONE. Moths with high contrast markings – that break up the shape of the body, like that of a zebra or giraffe – were best at evading predation at the start of the experiment. However humans learnt to find these prey types faster than moths with low contrast markings that match the background, like that of a stick insect or leaf bug. (more…)

Read More

Invasive Mussels Causing Massive Ecological Changes in Great Lakes

ANN ARBOR, Mich. — The ongoing spread of non-native mussels in the Great Lakes has caused “massive, ecosystem-wide changes” throughout lakes Michigan and Huron, two of the planet’s largest freshwater lakes, according to a new University of Michigan-led study.

The blitzkrieg advance of two closely related species of mussels—the zebra and quagga—is stripping the lakes of their life-supporting algae, resulting in a remarkable ecological transformation and threatening the multibillion-dollar U.S. commercial and recreational Great Lakes fisheries. (more…)

Read More