Climate change is already having adverse effects on ecology and wildlife around the world, and these problems are likely to worsen in the coming years. But much remains unknown. While many species, like the Arctic polar bear, will predictably be worse off when their natural habitat and food sources are depleted, other species will undoubtedly benefit, and for still others the fate could go either way. A typical example is rabbits.
It is known that there are more than 30 different species of rabbits including 305 different breeds distributed all over the world. Rabbits are one of the youngest domesticated animals, with some scholars tracing their domestication back to the French monasteries in the 6th century. At the time, Pope Gregory the Great decreed that rabbit meat could be consumed during Lent, leading to increased production in monasteries.
They are considered useful in many contexts and pests in others. For example, humans eat rabbits, use their fur for clothing (also in some types of wool), rabbit feet are popular lucky charms, and therapeutic proteins are extracted from rabbits for medicinal purposes. Rabbits also share some hereditary traits with humans, including some common diseases, making them popular for use as test animals in scientific experiments.
At the same time, rabbits can be a major nuisance and even an environmental hazard. Most of us have seen rabbits invade our home gardens, eat homegrown vegetables, or gnaw flower petals. They can be so troublesome that they threaten entire plant species in their vicinity.
Rabbits can be particularly problematic on islands. For example, in the Canary Islands off the coast of Morocco, European rabbits pose a threat to local vegetation would exacerbate ecological problems there.
According to the study, rabbits in Tenerife (one of the Canary Islands) are more likely to thrive in the drier, more temperate zones. As temperatures rise, alpine areas will see less snow at higher elevations and become more rabbit-friendly. On the other hand, higher rainfall correlates with lower rabbit populations in the region, so changes in drought or storm patterns could prove important.
Other studies show that rainfall benefits rabbits by increasing the amount of foliage they have available to eat. For example, a study of Baja California rabbits over 10,000 years describes a “Baja Bunny Boom” effect, in which El Nino weather patterns produce greater rainfall and, as a result, higher rabbit populations compared to other time periods.
Due to climate change, precipitation patterns are likely to vary around the world. Just as some regions experience more precipitation due to more extreme weather events, others will experience longer periods of drought due to drought.
At higher temperatures, rabbit production becomes more demanding, which means higher costs for farmers in the form of fans, air conditioning or other cooling strategies. Reduced fertility in rabbits is a result of hot temperatures (which appears to be the case in humans as well). Litters tend to have fewer rabbits, birth weights are lower, and mortality rates among young are higher.
If rabbit production becomes more expensive, it could impact medical research and also countries like Egypt, where rabbit meat has become an important part of the food supply and local economy.
Rabbits sometimes struggle with higher temperatures because they only have a few sweat glands. Still, some species, notably rabbits, thrive in arid desert climates. Others, like the white mountain hare, whose fur changes color in the warmer months, may be at increased risk from predators when snowfall patterns change.
One study found that at around 32 degrees Celsius
Parasites in dirt that rabbits ingest can also increase at higher temperatures. This could reduce rabbit populations depending on how their immune systems respond, and may also impact other livestock and even humans, as young children also get sick playing in the dirt.
This is another area where the impacts of climate change on both humans and wildlife are likely to be diverse and multifaceted. Rabbit populations in some areas, like the Canary Islands, may well be increasing, although these cute white mountain hares are becoming harder and harder to find. All in all, the effects look harmful. Some estimates suggest that more than two-thirds of rabbit species could be threatened by climate change.
Because of the many uses of rabbits by humans, as well as the threat they pose to various forms of vegetation and therefore ecosystems, there will be many knock-on effects – some good, some bad – of rabbits coping with the ongoing challenges associated with climate change.