June 14, 2011

Warmer Spring Causing Survival Issues In Cows

As a gradually warmer climate emerges, researchers are observing flowers blooming sooner and birds breeding earlier in the year, but is it may also be affecting the breeding habits of larger mammals.

A new study of the United Kingdom's Chillingham cattle, published in the British Ecological Society's Journal of Animal Ecology, reveals climate change is upsetting the breeding habits of those cattle, specifically resulting in fewer calves surviving, The Telegraph is reporting.

Examining 60 years of data, the researchers found the biggest change was the increasing number and proportion of Chillingham calves born during the winter. And when they compared winter births with UK Met Office weather data, they found warmer springs nine months earlier were responsible.

A team led by Dr. Sarah Burthe of the Centre for Ecology & Hydrology were able to use the cattle to discover more about the impact of climate change on phenology, the timing of key biological events, in mammals. Information about these cattle has been collected since 1860 with the help of Charles Darwin.

According to Burthe, "Charles Darwin encouraged the owner to keep records of births, deaths and "Ëœnotable occurrences', but he couldn't have anticipated that these records could contribute to our understanding of the biology of global climate change."

Datasets are crucial tools for studying climate change, yet very few exist. "The Chillingham cattle data are unique and, as far as we know, the longest mammal phenology dataset in the world. It's an amazing dataset."

The Chillingham cattle were once domesticated but are currently feral, kept wild and unmanaged. They have distinctive white coats, red ears and horns. These cattle also differ from most other UK mammals because they give birth throughout the year, not only during spring and summer.

Calves being born in the colder weeks of winter is bad news for the herd, "Winter-born calves don't do very well and are more likely to die before they reach the age of one. This suggests that the cattle are responding to climate change but this is having a negative impact on them," Burthe explained.

The results are important because they show that even species able to breed year-round, which might be expected to cope better with environmental change, are altering the timing of their breeding schedules and these changes are having negative consequences.

The study fills gaps in the understanding about phenology and climate change in an important group of animals. "Feral animals are often important components of ecosystems and used as tools for managing habitat, but we know very little about how they might respond to climate change."

"Understanding the consequences of phenology change and how widespread these responses are, even in relatively flexible species such as cattle that are able to breed year-round, helps us to predict the potential magnitude of changes caused by a warming climate."


On the Net: