Migrating birds are arriving at their breeding grounds earlier as global temperatures rise, a new research said.
The study has been done by the University of Edinburgh study, which looked at hundreds of species across five continents.
According to the research, birds have reached their summer breeding grounds on average about one day earlier per degree of increasing global temperatures.
The time they reach their summer breeding grounds is significant, because arriving at the wrong time, even by a few days, may cause them to miss out on vital resources.
This, in turn, would play a vital role in offspring hatching and their survival.
Birds with long-distance migration are said to suffer the most as other birds gain an advantage by arriving at breeding grounds ahead of them.
The researchers examined records of migrating bird species dating back almost 300 years.
The study examined how various species, which take flight in response to cues such as changing seasonal temperatures and food availability, have altered their behaviour over time and with increasing temperatures.