(July 9, 2015) UBC
research shows world’s monitored seabird populations have dropped 70 per cent
since the 1950s, a stark indication that marine ecosystems are not doing well.
Michelle Paleczny, a UBC master’s student and researcher
with the Sea Around Us project, and co-authors compiled information on more
than 500 seabird populations from around the world, representing 19 per cent of
the global seabird population. They found overall populations had declined by
69.6 per cent, equivalent to a loss of about 230 million birds in 60 years.
“Seabirds are particularly good indicators of the health of
marine ecosystems,” said Paleczny. ”When we see this magnitude of seabird
decline, we can see there is something wrong with marine ecosystems. It gives
us an idea of the overall impact we’re having.”
The dramatic decline is caused by a variety of factors
including overfishing of the fish seabirds rely on for food, birds getting
tangled in fishing gear, plastic and oil pollution, introduction of non-native
predators to seabird colonies, destruction and changes to seabird habitat, and
environmental and ecological changes caused by climate change.
Seabirds tend to travel the world’s oceans foraging for food
over their long lifetimes, and return to the same colonies to breed. Colony
population numbers provide information to scientists about the health of the
oceans the birds call home.
Albatross, an iconic marine bird that lives for several
decades, were part of the study and showed substantial declines. Paleczny says
these birds live so long and range so far that they encounter many dangers in
their travels. A major threat to albatross is getting caught on longline
fishing hooks and drowning, a problem that kills hundreds of thousands of
seabirds every year.