This article has been reviewed according to Science X's editorial process and policies. Editors have highlighted the following attributes while ensuring the content's credibility: Although the main prey of spotted hyenas (Crocuta crocuta), migratory ungulates such as blue wildebeest (Connochaetes taurinus), now spend substantially less time within hyena territories than they did 30 years ago, hyena clans in the central Serengeti have remained largely stable. In a study published in the journal Ecosphere, scientists used one of the world's longest-running datasets on a large carnivore, spanning three decades and including thousands of individually known hyenas across multiple generations.
They investigated how climate-related changes in prey availability within clan territories influence hunting opportunities and, ultimately, the hyena population in Serengeti National Park, Tanzania. Over recent decades, rainfall has increased across the Serengeti. This change in rainfall is suspected to have influenced the movement patterns and distribution of large herds of migratory prey, as it reduced the time these large prey herds now spend within central spotted hyena clan territories.
Whereas between 1990 and 1994 migratory herds were present within clan territories for around 12% of the year, this had consistently declined to only about 7% between 2015 and 2019. Consistent with the decline in the presence of migratory prey within clan territories, the number of observed feeding events also declined over the study period. However, the scientists found that Serengeti hyenas continued to feed predominantly on migratory prey species and have not gradually switched to resident prey species, which occur at much lower densities and would be insufficient to sustain entire clans.
"Spotted hyenas are what ecologists call central-place foragers," explains Dr. Mellina Sidous, lead author of the study. "They cope with seasonal fluctuations in prey availability by commuting between their clan territory and the areas where migratory herbivores are currently concentrated.
These commuting trips are particularly common among females with young cubs, because the cubs remain at the communal den and cannot accompany their mothers." These foraging trips can last up to a week and involve journeys of up to 150 kilometers (93 miles). Hyenas undertake these long-distance trips only when migratory prey are absent from their own territories. Despite fewer feeding opportunities within their territories over the past three decades, two of the three study clans increased in size.
"Our results suggest that spotted hyenas are currently able to buffer the decrease in local prey availability," say the two senior authors Dr. Sarah Cubaynes, scientists at the Leibniz-IZW and CEFE. "Their behavioral flexibility appears to allow them to compensate for reduced hunting opportunities within their territories," adds Dr.
Extract — continue reading at the source.
