In 2000, the Canadian Wildlife Service (Environment Canada) initiated a project to survey tern colonies in Newfoundland. Terns are a small gull-like seabird which are locally referred to as Stearins in Newfoundland.
Three species of terns nest along the coast of Newfoundland: Common Terns, Arctic Terns, and Caspian Terns. A fourth species, the Roseate Tern, is listed as Endangered by the Committee on the Status of Wildlife In Canada (COSEWIC). These species do nest in Newfoundland but the health of Roseate Terns elsewhere is directly linked to the health of the regional population of Common and Arctic Terns.
Starting in 1999 the Canadian Wildlife Service undertook the task of conducting tern surveys in all four Atlantic provinces. This was done because surveys were vastly out of date and this province had not been surveyed since 1973. There were concerns that all four species may have been declining as terns are threatened by increased human presence in the coastal zone, as well as from predation by gulls.
Human development is reducing the number of islands available for these birds to nest on and increased access to islands may increase their exposure to direct disturbance from humans. Gulls have adapted to particular human activities by taking advantage of artificial food sources, such as fishery discards and open refuse dumps.
Many more gulls
As a result gulls have increased dramatically since the start of the last century. This trend may be starting to change as fisheries and land fill closures have reduced the amount of artificial food available to gulls. However, these artificially augmented gull populations continue to thrive in many places, often at the expense of other species such as terns upon whom they may prey.
There are two components to the surveys.
"We conduct plane surveys to locate colonies from the air, and we then try to visit as many of the colonies on the ground to actually do nest counts," says Wildlife Biologist Andrew Boyne.
"We are surveying all coastal seabirds, although we are focussing on terns. Our estimates for other species are more coarse but we do have information on the locations of gull, kittiwake, and alcid colonies."
Over the three years of the surveys, 250 tern colonies have been identified along the entire coast of Newfoundland and it is estimated to be approximately 22,500 individual terns while conducting aerial surveys.
Aerial counts tend to underestimate the number of individuals so it is likely that the numbers are much higher than that.
Two local incidents
While in the St. George's Bay area there were two incidents wildlife biologists took note of.
At one colony at the base of the Port au Port Peninsula a local resident was quite concerned about their presence on the island.
"He was concerned we were disturbing the birds. He was quite right in that human disturbance at breeding colonies is certainly an issue for these birds. The time that we were in the colony was quite short and controlled so it is unlikely that we would have had an impact on the colony. It is good to see that people are protective of the birds."
The flip side of this is that at Point au Mal there was another colony where they found the carcasses of 14 terns which had recently been shot.
"This is quite disturbing. We would like to think that this was an isolated incident that was conducted by people who were uninformed of the significance of these birds."
From Argentina to the Arctic
One of most disappointing things about it was that of the 14 birds, two of the birds had been marked with metal leg bands and small orange leg flags. It turns out that these two birds were banded by researchers in Argentina. Terns actually have the longest migration of any animal on earth. Some Arctic Terns migrate from the tundra of northern Canada to spend the winter off the Antarctic ice pack. This means these small birds migrate over 35,000 km a year. That is roughly the circumference of the earth.
"It is sad to think that these birds were able to travel all this way to breed in Newfoundland only to be shot once they arrived. Hopefully with more education people will learn to appreciate these beautiful small birds and incidents like this will no longer occur."
It is difficult to compare results to the last surveys conducted in 1973 because it was such a long time ago and the methodologies were slightly different. In 1973 the whole island was surveyed in one year so the effort wasn't as intense as the recent three year study.
"We feel, and this is preliminary to some degree, that tern populations appear to be relatively healthy but there has been quite a bit of colony movement in the last 30 years. This is not surprising considering the time period between surveys and that terns are known to change nesting sites regularly, often without apparent reason."
The Canadian Wildlife Service has recently completed a three year survey in Newfoundland on the bird species, Tern. This is the first time such a survey has been done since 1973.
