The population of animals is decreasing due to their risky food search strategies



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Magellanic penguins living in Argentina can easily find fish, indicating that the food supply options are good for them. Credit: Emily Shepard

A study using animal technology to measure food consumption in four very different wild vertebrates has shown that animals using a high-risk strategy for finding rarer foods are particularly susceptible to extinction because they do not feed their young ones before they die .


In a first study of this kind, a team of researchers led by Swansea University used electronic tag size symbols to record the movement of many individual condoms, cheetahs, penguins and sheep in Argentina, South Africa and Northern Ireland for an annual period.

Named "Daily Diary", the labels record a multitude of data – all from the animal's minute movements through space and time, to the temperature of their environment and light.

The results of the measurements were used to measure:

  • The probability that every animal finds food.
  • Size of food items.
  • Efforts to find food.
  • Striving for all other activities, such as rest, play, etc.

Professor Rory Wilson, Swansea University, the world's leading expert on animal movement and lead author of the study, said: "We know that the animal population worldwide enjoys a hit, with the most charismatic animals, such as left and cheetahs, among the worst, but until now it was not clear why.

"Our study has shown that animals using a high-risk gambling strategy to find food, such as lions and tigers, who need to look for a long time before they meet and find a prey, are more likely to not accumulate energy, which they need in the breed, compared with animals that adopt a low-risk gambling strategy, such as herbivorous animals such as zebras. "

Magellanic penguins living in Argentina can easily find fish, indicating that the food supply options are good for them. Credit: Rory Wilson, Swansea University

The average time for survival of young people in food without food depends on their size (larger young people can survive even longer), but newborn or newborns can not live without food for more than a few days.

The study highlights the catastrophic results of these animals by using a high-risk strategy for finding foods by comparing two types of penguins. While magellan penguins living in Argentina can easily find fish, indicating that quotas are good for them, African penguins, whose population has been declining in southern Africa for decades, have very small quotas for their food supplies.

"It seems that commercial fishing has changed the rules of the game to the worse for African penguins. When animals live a rare prey, there are also minor changes in the ecosystem resulting from human activity, straw that breaks the camel back in terms of breeding success, and this it seems to be an example of an African penguin whose population is now only 1% of what was 100 years ago, "said Professor Wilson.

African penguins, whose population has been declining in southern Africa for decades, have very poor opportunities for their share in discovering food. Their population now is only 1 percent of what was 100 years ago. Credit: David Grémillet

Researchers now hope their model can be used to predict the wealth of species all over the world, which could be crucial in designing conservation plans.

The article entitled Luck and Finding Food, which affects individual performance and trajectories of the population, is published in Current biology.


Explore also:
After a bad winter in the ocean, women's magellanic penguins are most affected, according to studies

More information:
The meeting in the discovery of food affects the individual performance and trajectories of the population, Current biology (2018). www.cell.com/current-biology/f … 0960-9822 (18) 31363-0

Reference number:
Current biology

Provided by:
Swansea University

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