Research shows that hyena dogs now give birth about 22 days later than in the 1990s. It is an emergency measure inspired by climate change, which – unfortunately – turns out badly.

Climate change is not in the future. Climate change is happening now. And the consequences are visible and tangible in many places, for example in the form of melting (sea) ice, retreating glaciers, more frequent heat waves and other weather extremes. And climate change has also affected the animal and plant worlds, with some species even making desperate efforts to adapt to the new normal. For example, we know of some plant species that – because spring starts earlier and earlier – they sprout and bloom earlier. And that in turn can lead to changes in the rhythm of life of, for example, birds and insects that depend on those plants for their food.

Higher up the food chain

All of these are striking changes, clearly driven by climate change, but which take place quite low in the food chain. But anyone who thinks that climate change is only felt there is wrong, researchers now say in the magazine Proceedings of the National Academy of Sciences† In the research article, they show that animals higher up in the food chain – such as larger predators – are also forced to adjust their rhythm of life as a result of climate change.

Hyena dogs

The research paper in question deals with African wild dogs (also known as hyena dogs). The scientists looked at data collected on 60 packs of wild hyena dogs living in Botswana over a period of 30 years. The researchers looked in particular at the moment when the hyena dogs gave birth to their young. And that leads to striking conclusions. In 1989 the hyena dogs had their young on average 22 days(!) earlier than is the case today. “That shift has meant that temperatures at due date have remained relatively stable,” the researchers write in their article

In other words, the hyena dogs gave birth 22 days later than in 1989, but still at the temperature at which they gave birth 30 years ago. According to the researchers, it shows that the hyena dogs had to postpone their due date in order to give birth to their young at their preferred temperatures.

About hyena dogs
Hyena dogs are distantly related to the wolf and are only found in Africa. They hunt there – in packs – on impalas, warthogs and other mammals. The hyena dogs reproduce every year, in the winter. The young then spend three months in the den with their mother before migrating and hunting with the pack.

It is clear that temperatures in the hyena dog’s habitat have changed. In thirty years, the average maximum daytime temperature has risen by no less than 1.6 degrees Celsius. And in the same time frame, the average maximum annual temperature has risen by 3.8 degrees Celsius. And those temperature changes have forced the hyena dogs to postpone their delivery. And because of that adaptation, they can give birth to their young at the same temperatures as 30 years ago.

From the rain in the drop

Well, you might think, then we don’t have to worry about those African wild dogs, because they’ll manage – with their great adaptability. But no, that kite is not going up, the researchers say. “It’s a ‘rain in the drip’ situation,” said researcher Briana Abrahms. “African wild dogs have moved their due date a bit (…) but that leads to higher temperatures in the period after the birth of the puppies and lowers their chances of survival.”

Bad news

And with that, for the hyena dogs – despite their frantic efforts to adapt – climate change is very bad news. Because the species is already not in such a good shape; their numbers have declined in recent decades due to habitat fragmentation and destruction. And it is estimated that there are only 1400 adult hyena dogs left in the wild.

The researchers hope their study prompts other scientists to take a closer look at other larger mammal species as well, to see how they respond to climate change. “Large predators play exceptionally important roles in ecosystems,” says Abrahms. “But we still have a lot to learn about the implications of climate change for these animals. Major climate-induced changes such as we have now found may be more common among predators than we thought.”