Nesting hawks & rare woodland butterflies


The search for new MAPS sites to join our existing Maplewood Bog and Rock Ridge stations has begun. The process is challenging, particularly here in the Frontenac Arch where ‘disturbed’ habitats with pronounced edges can be hard to find. The edges are important as this is where adults and young congregate during post-breeding dispersal, which is key to evaluating annual productivity. The heavily forested Frontenac region also tends to feature open understoreys with little shrub or sapling growth – not suitable for capturing birds using mistnets. Therefore the search feels something akin to looking for a needle in a haystack: a daunting job, to be sure, but not impossible. A needle we shall find!

Trout Lilly

Ontario Parks has been a tremendous supporter of FBS and have made a number of useful site suggestions for a second MAPS station within park boundaries. I will be checking out these various sites and will report on them as they are visited. I searched a good candidate site in a small portion of Frontenac Provincial Park today but unfortunately found nothing suitable for a MAPS site. Despite this I did have an incredible outing with some noteworthy discoveries.

Eastern White Pine

Today’s meander took me through a patch of mixed forest dominated by Eastern White Pine. Ruby-crowned Kinglets, Pine Warblers and Yellow-rumped Warblers were numerous in the canopy while newly arrived Eastern Towhees called from small rock outcrops. I came upon this excavation that was recently created by a Pileated Woodpecker, a common inhabitant of Frontenac Park. The sap was running quite thick and apparently attracted and drowned a considerable number of springtails along with a few other insects.

Woodpecker excavation

I spent an hour or two exploring the margins of many small/medium wetlands for good edge habitat but managed to find nothing of any use to a would-be bird bander. I did, however, find an impressive showing of early spring wildflowers such as Trout Lilly, trillium, hepatica, Bloodroot, Dutchman’s Breeches and Spring Beauties. After snapping a few photos, I decided to head for an area of mature forest en route back to the main road.

Red-shouldered Hawk nest

This is when things got interesting! This Red-shouldered Hawk nest was rather easily discovered in a mature Yellow Birch within a steep valley of mature hardwood forest. The adults were nearby and quite displeased with my presence! This is the first nest found by FBS in 2010, which is consistent in habitat and timing with the first nest of 2009 – a Red-shouldered Hawk nest on Canoe Lake Road. I quickly left the nest site to avoid unnecessary disturbance to the hawks, which seemed to be in the beginning stages of nest renovation.

There is a considerable amount of mature deciduous forest in Frontenac with some century old stands present. These forests are ideal for several species of conservation concern such as Cerulean Warbler and Red-shouldered Hawk. However, the ‘real’ biodiversity in these forests is exhibited by its plant and insect communities.

Woodland stream

With forthcoming Louisiana Waterthrush surveys in mind, I ambled down the bank to check on the water level and flow of this stream that courses through the forest. This past winter was the driest in decades and the lack of spring rainfall has further compounded the dry conditions. The result is very low water levels and weak flow of many streams in the park. I am hoping that we will get some decent rain in the coming weeks as the current picture for breeding Louisianas is bleak. There will be more to follow on our efforts to inventory the park’s streams for Louisiana Waterthrush.

West Virginia White at rest (finally!)

The stream valley was hopping with early spring activity and the most apparent of the beasts were these ghostly-white butterflies, which I suspected might be West Virginia Whites (Pieris virginiensis), a species of Special Concern in Canada. An impressive number of these eye catching butterflies were observed fluttering about near the forest floor. This species is known to occur in Frontenac Park where suitable habitats are found. West Virginia Whites occur in mature moist deciduous forests in isolated pockets of southern and central Ontario. They are known to occur at about 50 sites in the province and were once classified as an Endangered Species (1977). The West Virginia White is one of the earliest butterflies to emerge in spring when the adults seek out emerging toothwort, which their larvae feed on exclusively. I will be watching closely for this species during all of the work in mature forest coming up in May.

West Virginia Whites

Often one finds the most interesting things when looking for something else. The search for new MAPS sites will continue……

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s