Swallow research

The Nature of PEI by Gary Schneider

Tree swallow

One of my favourite birds is the Tree Swallow, back now in full force across the province. Each year I spend a lot of time worrying that they might not show up again in the numbers that I’m used to. To watch these wonderfully acrobat aeronauts has always been one of the highlights of my summers.

Insectivores such as swallows have been in decline for quite some time, probably a combination of destruction of both winter and nesting habitat, and the lower insect populations due to the use of agricultural pesticides. They spend winters in southern Florida and Central America, and long migrations always put birds at risk.

Tree Swallows are handsome birds, with a blue-black almost iridescent back and a bright white front. We do have other swallows, but they are relatively easy to tell apart if you look closely. Two other swallows found in the province are Bank Swallows and Barn Swallows. Both are being monitored across the region due to their declining numbers.

Bank Swallows are found almost exclusively along our coastline, where they dig nests into the bank. They have brown backs and a brown “necklace” above their white bellies. Barn Swallows are mostly found around—you guessed it—barns with openings that allow the birds to nest inside on flat parts of the structure. They have longer, forked tails, and while their colours can be similar to the Tree Swallow, they have a much more patterned head and usually quite a bit of orange-brown in their belly feathers.

Tree Swallows really stand out on their own. They are strictly a cavity nesters, and since we seem to be having less and less natural cavities—though Fiona might have changed that temporarily—they really benefit when people put up nest boxes. And this is one of the species for which the effort you put into constructing, placing, and cleaning a nest box usually pays off. We have placed nest boxes at school plantings and when naturalizing areas and are often surprised at how quickly they become occupied. We also have them placed around the Macphail Woods nursery and there is always at least one pair using them.

Nest boxes are easy to construct, though the entrance hole must be the proper size and boxes should be cleaned each spring. They should be in place well before the birds come back to nest—usually around early May.  

While we’re not sure of the exact numbers of Tree Swallows in this province, some watershed groups are helping with this research. Last year the Kensington North Watershed Association built and placed boxes across the watershed. Matt Ginn, a biologist with the province, bander Fiep de Bie, and community volunteers banded 70 birds—a combination of adults and juveniles. This year, the Trout River Environmental Committee has joined in the effort (along with other watershed groups) and produced the excellent Cross-Watershed Tree Banding Booklet. 

The booklet contains lots of information on Tree Swallows, including very detailed plans for constructing nest boxes. This is a great resource for anyone interested in these wonderful birds.

You can get a free copy to download by going to troutriverec.ca/tag/tree-swallow/

Banding started in early June this year, and there were already some recaptures of birds that had been banded last year. Thanks to the watershed groups, all the banders, volunteers, the provincial Department of Environment, Energy and Climate Action and the PEI Wildlife Conservation Fund. This is important work that will provide useful information over the long term. It is great to see these types of collaborative efforts. Well done.