Seabirds are at risk due to the competition they face from the fishing industry for food, according to a study.

Experts said there has been a 70% decline in seabird populations over seven decades due to a combination of the fishing industry, pollution and habitat destruction.

Scientists from the University of Aberdeen looked at two timeframes – 1970-1989 and 1990-2010 – to assessthe degree of competition seabirds faced for prey species such as anchovy, sardines, mackerel, squid, krill and crustaceans.

The team then estimated the annual consumption of those prey species for 276 seabird species based on population counts and models and compared it to the annual catches by fishing boats as contained in the Sea Around Us world database.

The scientists found that the total annual seabird consumption decreased from 70 to 57 millions of tonnes between 1970-1990 and 1990-2010, while annual fishery catches increased from 59 to 65 millions of tonnes over the same period.

Dr Aurore Ponchon, who co-led the study, said: “Our research shows, that despite the decline of the world seabird community between 1970-1989 and 1990-2010, competition with fisheries remained sustained. This competition was even enhanced in almost half the oceans.

“This enhanced competition, in addition to other factors such as pollution, predation by invasive species on chicks, the destruction and changes in their habitat by human activities and environmental changes caused by climate change, puts seabirds at risk, making them the most threatened bird group, with a 70% decline over the past seven decades.

“This study calls for an improved management of the world’s fisheries to alleviate competition pressure on seabird populations.”

The study, published in Current Biology, also involved scientists from the University of British Columbia and the French National Centre for scientific research.