Yellow-throated Vireo (Seabrooke Leckie)

The July-early August period of the Monitoring Avian Productivity & Survivorship (MAPS) season is important to our annual assessment of productivity rates. During this time a critical shift occurs from the main nesting period for adults (May-June) and the post-breeding dispersal/pre-migration period (July-August). Some species are still nest building and incubating – mostly late breeders (Cedar Waxwing, American Goldfinch) and those raising second broods or first broods after nest failure. We are able to sample the year’s productivity (nest success) for many species during visits 4-7 when the juvenile or hatch-year birds are first introduced into the population.

Pileated Woodpecker (S.Leckie)

Blue Lakes (BLAK)

On July 7 we operated BLAK for the fourth session this season. We ended the day with 13 individuals captured, all of which were newly banded. Notable amongst the birds banded were four Ovenbirds, which have been relatively scarce this year, and two adult Yellow-throated Vireos. Only two of the birds captured were young birds, a Rose-breasted Grosbeak and a Hairy Woodpecker.

Visit 5 was completed on a calm, clear mid-July morning. We were a little shocked by how quiet it was as just three birds had been captured until the final net check when a young Black-capped Chickadee was extracted from net 12. The lone highlight of the record slow morning was our second-ever Pileated Woodpecker!

Hatch-year Yellow-bellied Sapsucker (S.Leckie)

Maplewood (MABO)

Activity at MABO has been a little higher than at BLAK, although markedly less so than in previous seasons. We captured 22 birds on July 8, which was followed by a total of just 11 on July 20. We’ve banded a decent number of young birds during the two visits including individuals of Veery, Scarlet Tanager and Yellow-bellied Sapsucker, among others. Since we started in 2009, MABO has produced substantially more recaptures than any other station. So far this year we’ve recaptured 13 at BLAK, 13 at RRID and 34 at MABO.

Red-winged Blackbird (S.Leckie)

Rock Ridge (RRID)

While MABO always seems to perform best of the three stations for adults in June, Rock Ridge typically outshines the others for dispersing adult and young birds in July and early August. A total of 13 birds were sampled on July 9, which was followed by a season-high total of 28 on July 19. This site is located on a high ridge along a peninsula that is bound by a large lake on three sides – attributes that naturally funnel birds on the move. An excellent diversity of species were detected and captured on July 19, which included a respectable number of young birds. Common Grackles, Red-winged Blackbirds and American Robins have been the primary species involved so far but this should changeover to warblers and other small passerines during visits 6 and 7, which are due in the next two weeks.

Hatch-year Blue Jay (S.Leckie)

Sharp-shinned Hawk (Derbyshire)

The third round of visits for the 2011 Monitoring Avian Productivity & Survivorship (MAPS) season were completed on June 27 (BLAK), June 29 (MABO) and June 30 (RRID). The weather in June has actually been rather normal and lacking in extended periods of unusual temperatures or precipitation – good for us and good for all the passerines raising young! A total of 17 (9 new, 8 recaptures) birds were captured at MABO during visit 3, the highlight of which was the second-year Sharp-shinned Hawk pictured above – a first for our MAPS efforts to date. Also of note was the recapture of five Veery from previous seasons, including three from our first couple of visits in June 2009.

Purple Finch (Seabrooke Leckie)

The BLAK station was the “winner” of Round 3 as 25 birds (20 new, 5 recaptures) were captured here during the visit. All five recaptures were of birds banded earlier in the 2011 season. We banded a nice variety of species, including another male Black-throated Blue Warbler, a Yellow-rumped Warbler and a Hermit Thrush. The highlight though was the male Purple Finch extracted from net 7 around mid-morning – another first for our MAPS program! This species does occur regularly at all three stations but are so strictly attached to the upper canopy that they will always be only rarely captured.

Weather at RRID was calm and clear with pleasant temperatures. A total of 17 birds were sampled by our mistnet array (15 new, 2 recaptures). We recaptured a Field Sparrow that was originally banded on June 20, 2010 as an After second-year male. It’s becoming clear that the return rate of adults is very low at RRID, especially compared to MABO. Habitats and species composition differ greatly between stations, which will certainly present some interesting topics for further study once a few more seasons of data are compiled.

Here is a quick chart that describes an apparent decline of the adult population at all three stations since 2009 (Only 2010-2011 for BLAK). The graph was generated using total captures (newly banded birds and recaptures) for visits 1-4 by year and station. It would be such a tremendous resource if we had more MAPS stations across Ontario to facilitate local and regional comparisons of vital rates. Unfortunately, in marked contrast to the United States, participation in Canada and in Ontario has been very low. The development of a coordinated and standardized effort to monitor breeding bird demographics in the province would be a major asset for biologists to detect and understand forces affecting landbird populations – now more than ever with advancing climate change.

Adult male Prairie Warbler (D.Derbyshire)

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Prairie Warbler (Dendroica discolor)

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Nidiologicals – Peck and James (1987) and Nolan,V.,Jr., E.D.Ketterson, and C.A.Buerkle (1999)

Habitat – Dry, early successional shrubland habitats ranging from pine plantations, dunes, mangroves, barrens, clearcuts and abandoned fields.
Microhabitat – Cup nest usually well concealed in upper crotches of shrub
Spring arrival – Early to mid May (Ontario)
Average nest height – .6m-.9m
Nest builder – Female only
Average # of broods/season – 1-2 (variable with latitude and local conditions)
Average egg laying date – 8 June-19 June (Ontario)
Average clutch size – 3-5 eggs
Incubation period – Average 12 days
Egg colour – White to greenish white with variable brown spots, usually wreathed at larger end.
Incubation – Female only
Brown-headed Cowbird host – Yes

Prairie Warbler habitat (nest site in foreground)

The Prairie Warbler is a rare but regular breeding species in Ontario. It is estimated that about 300 pairs occur annually in the province, although there is some evidence of recent decline due to habitat succession of granitic rock barrens along the edge of the southern shield region. We’ve been surveying and studying Prairies in Frontenac Provincial Park for the last two years and have found a small but apparently healthy population in open barrens with scattered young trees and pockets of dense shrub cover. The above photo was taken within the core breeding area, which is about 20 hectares in size and characterized by low tree cover, exposed rock, dense ground vegetation and thick patches of vibernum sp. and junipers. Most Prairie Warbler territories here are associated with sloped shoreline edges of beaver ponds and lakes, which may be a function of denser shrub growth occurring in lower lying areas.

Shrubs along rocky slope (nest site in foreground)

This photo shows a typical nest site along a rocky slope where Downy Arrowwood (Viburnum rafinesqueanum) proliferates. Four nests have been found so far this summer and all but one were positioned near the top of a viburnum at heights between .7m-1.3m. All four nests have been located along slopes ranging from gentle to sharp and with no apparent preference for aspect.

Prairie Warbler Nest with eggs

Prairie Warbler nests resemble those of the Yellow Warbler (Dendroica petechia), a fairly close relative but less common inhabitant of the rock barrens. Prairie Warblers favour hot and dry environments while Yellow Warblers tend to occupy wetter shrubland habitats with a more flexible tolerance for shade/canopy closure. This nest with four eggs was discovered on June 26 when a female was flushed from a small clump of viburnum. When incubating female Prairie Warblers notoriously sit tight and only flush when very closely approached.

Nest in viburnum

This is a shot of the same nest within the shrub. Prior to nest searching this season I was anticipating that Ground Juniper (Juniperus communis) would be the most common host plant for nests but it seems that the viburnums are more abundant and probably preferred here. They are a stout and sturdy shrub with woody main stems and branches, while the leaf cover provides excellent concealment and weather shielding from all sides. The only non-viburnum nest was located in a lonicera sp. that grew within a large clump of Downy Arrowwood.

Prairie Warbler nest with five young (5-6 days old)

Two of the four nests were found by patiently following adults carrying beakfulls of plump, green caterpillars. One of our colour banded males (nickname “Whitey”) led me to this nest with five young. Thanks are due to Julie Zickefoose for helping Seabrooke and I age these nestlings. These little prairielets were identified as being 5-6 days old and only a few days away from leaving the nest.

Incubating female

This female was photographed incubating on June 26. When I returned five days later I was disappointed to find that the nest had failed, probably due to predation. Common Grackles, Blue Jays and snakes would be the most likely nest predators in the barrens. I’ve twice found Ribbon Snakes (Thamnophis sauritus) above the ground within shrubs here. On the upside it appeared that the female, or perhaps a different female, was preparing to rebuild within the territory or perhaps even reuse the failed nest. The attached male (also colour banded) was singing vigorously while the female inspected forks of shrubs and called softly. On two occasions she was observed for five-minute periods shaping and touching up the failed nest. Hopefully the second attempt will fair better than the first!

Scarlet Tanager (S.Leckie)

Our third season of M.A.P.S is now approaching its halfway point. Our second round of visits to the three stations was a little more active than the first, especially at Blue Lakes (BLAK) and Maplewood (MABO). This striking male Scarlet Tanager (Piranga olivacea) was one of 23 birds captured on June 16 at MABO. Veery was the most abundant species captured that day followed by the ubiquitous Red-eyed Vireos – the most prolific forest songbird in the Frontenac Arch.

White Admiral (D.Derbyshire)

After capturing just 10 individuals in early June at BLAK, we expected another quiet day when we set the nets up at dawn on June 15. Perhaps the fairer weather helped as the vireos finally showed up and a bunch of other species seemed to be more evident. We ended the day with a meager but respectable 15 birds captured. Butterflies and other non-avian critters seemed to catch our attention throughout the morning, including the White Admiral (Limenitis arthemis) pictured above – a personal favourite.

Five-lined Skink (S.Leckie)

There is no substitute for sitting patiently and quietly when you want to find wildlife. During our first visit a couple weeks earlier we had a Smooth Green Snake approach us at the banding station. During our next visit while I was out on a net round, Seabrooke was approached by this adult Five-linked Skink (Plestiodon fasciatus) at the station! We also had a brief look at a blue immature individual just yesterday at the same spot.

Black-and-white Warbler (D.Derbyshire)

Normally I pull the plug on any planned M.A.P.S visit when the forecast indicates a 50/50 or greater chance of precipitation – too risky for me. However, I had little choice with visit 2 to Rock Ridge (RRID) on June 17. There was a brief 30 minute shower near dawn, which delayed net opening, but the rest of the morning was generally just damp and cloudy. We closed slightly early due to the forecast late morning thunderstorms – don’t want to be caught in that when a couple of kilometres out on Big Clear Lake. We noted much more bird song and chatter on this visit compared to our first but it seemed that the dreary weather was limiting bird activity. We ended the abbreviated visit with just 7 captures but left feeling encouraged by the apparent increase in numbers of expected species, particularly Black-and-white Warblers and Eastern Towhees. We caught an Ovenbird, which was weird for rock barren habitat. Even more surprising was the Prairie Warbler that sang from two positions at opposite ends of the study area throughout the morning. I’ve already picked out his colour bands so hopefully he will be there when we return….

Spruce/tamarack bog in Frontenac (click to zoom)

Yellow-bellied Flycatcher (Seabrooke Leckie)

Lots of updates to share but no time or energy to write anything at length. However, I couldn’t resist sharing news from this morning of a territorial Yellow-belled Flycatcher (Empidonax flaviventris) , which sang constantly from a good size Black Spruce/Tamarack bog in Frontenac Provincial Park. The water surrounding the bog is quite deep and probably full of monsters so I didn’t venture into the bog itself – though I did seriously consider crafting some sort of crude watercraft for the short passage. This would be the first breeding record for the park and one of only a handful for the entire Kingston region. Yellow-bellied Flycatchers are a true northern breeder, preferring moist boreal forest and peatland for nesting. I’ll have to add this to our ever expanding to-do list for Frontenac Bird Studies!

Eastern Towhee at Rock Ridge (Seabrooke Leckie)

In addition to all the stream hopping, nest searching, colour banding and biothon-ing, we are also well into our third consecutive season of the Monitoring Avian Productivity & Survivorship (MAPS) program. Our three stations have been a wellspring of data and ideas for the FBS program and a fundamental monitoring scheme for measuring the health and viability of local breeding bird populations. We launched the stations in 2009 and were pleased to find high numbers of adults at the sites. However, unusually wet and/or cold conditions in late spring/early summer of that year and again in 2010 appeared to contribute to low productivity (nest success) for two consecutive breeding seasons. This has been backed up by an apparent high nest failure rate detected by our nest searching efforts in both years. We hoped that things would begin to turn around in 2011 but unfortunately our results from the first of seven visits this year indicates record low numbers of adults – not unexpected given the lackluster output of young birds into the population in the preceding two years.

Blue Lakes (BLAK)

We began the season on June 4 at BLAK and found a mostly quiet woodland – far from the exuberant activity of even a year ago. We ended the day having captured just 10 individuals, although four of these were returns from previous years, which gave us some encouragement. For comparison we captured 24 individuals here during visit 1 on June 8, 2010. Numbers were down for most species with Red-eyed Vireo, Ovenbird, Black-throated Blue Warbler and Veery being the most lacking.

Big Poplar down at Net 8, MABO (S.Leckie)

Rock Ridge (RRID)

On the following day, June 5, 2011, we made our way to Rock Ridge in Frontenac Provincial Park. Once again, overall bird activity was considerably lower than in previous years, especially in the forest interior. A total of 10 birds were captured – again with 4 returns. This total is identical to that for visit 1 in 2010 but significantly lower than the 25 recorded in 2009. Black-and-white Warbler, Red-eyed Vireo, Scarlet Tanager and Field Sparrow are the species that seem to have declined here most heavily.

Male Yellow-bellied Sapsucker at BLAK (S.Leckie)

Maplewood Bog (MABO)

Our final stop for round one was to Maplewood Bog (MABO), which tends to be our busiest of the three stations. We captured 26 birds here during visit 1 in 2009, followed by 21 in 2010. After six hours of banding we arrived at, remarkably, yet another tally of 10 individuals!! We banded just four new birds and recaptured six returning individuals from previous years. The woods, once so abundant with thrushes, vireos and tanagers, were very quiet indeed.

Chestnut-side Warbler at BLAK (S.Leckie)

Our data from the MAPS program and our other studies appear to indicate a widespread downward trend in forest bird populations in the FBS study area since 2009. Factors driving populations are highly complex so we won’t be sounding any alarm bells or hitting the panic button just yet. Also, we know that populations are subject to periodic highs and lows in sync with naturally occurring but variable weather phenomena. We expect (and hope) that bird numbers will be gradually restored following breeding seasons with more favourable weather. Speaking of weather, the MAPS program is very well positioned to shed light on effects of climate change on breeding birds at the landscape, regional and even broader scales. It is unfortunate that there are so few MAPS stations in Ontario as it would be instructive to compare regional patterns and trends in vital rates in anticipation of shifting climate “normals”. All of this being said, there is still six more visits to each station in 2011 and a great deal more to learn.

May 30th was probably one of my top 5 most enjoyable days of fieldwork since Frontenac Bird Studies began. The weather was perfect, the biting insects were oddly subdued and I could scarcely walk 100m before needing to georeference some exciting critter. I saw many butterflies, moths, snakes and plants of note but the centerpiece was a wetland that Steve Gillis and I explored during our first biothon in July 2010. Below are two panoramic views of the swamp from the south and east respectively (click to enlarge).

The wetland is fairly large by frontenac standards, about 9 acres in total area. It is distinctive in having a small raised island of live trees (mostly pine) surrounded by a flooded lowland dotted with snags and fallen trees. Surrounding the wetland is mid-successional oak-maple forest with scattered mature trees, an open understorey and with ground cover dominated by grass. The area was absolutely teeming with cavity nesters – Northern Flickers, Hairy Woodpeckers, Yellow-bellied Sapsuckers, Great Crested Flycatchers and White-breasted Nuthatches mostly. Apparently the area is so irresistible to Common Grackles that they were also nesting in cavities 10-15m above the water – an unusual choice for them (1.8% of nests reported to Ontario Nest Records Scheme n=2652).

At the far north end of the swamp were two large platform nesting species – Osprey (1 nest) and Great Blue Heron (3 nests). These and the all the cavity dwellers put on quite a show! The bordering woodland was also active with Cerulean Warblers, Red-shouldered Hawks, Yellow-throated Vireos and a single Olive-sided Flycatcher being the most noteworthy. The Olive-sided is the first I’ve seen in the region and probably a migrant, although suitable is available north of the park closer to highway 7. You can hear it singing in the video clip above (quick-three-beers) along with the odd Cerulean Warbler.

The birding at this site in July of last year was less memorable, probably due to the fact that it was during a mid-afternoon in July. However we did spot a pair of Red-headed Woodpeckers that day (Melanerpes erythrocephalus) – a rapidly declining species (Threatened status) in Ontario. It turns out that the species has been retracting from many parts of its range but heavily in Eastern Ontario. Our observation was the second of only two documented breeding records for Frontenac Provincial Park, although breeding evidence was not officially obtained in 2010. I bookmarked this as a target for 2011 and am pleased to report that it took me less than 30 minutes to confirm an active nest site this past Monday!

Adult Red-headed Woodpecker near cavity

RHWO Nest Site (near top of snag just underneath foliage)

Their active behaviour and brilliant high contrast of their plumage made them easy to track and observe within the open wetland. An adult called repeatedly from the west end of the swamp but rarely approached the nest (the male?). The other adult, presumed to be the female, made frequent trips to a cavity near the top of a 14m tall snag close to the southeast shoreline. The video at the beginning of this post highlights some of the activity at the nest site, which seemed to be exclusively short incubation sessions as no excavation or food carrying were noted. We will return to this site again in the next week or two to check on its progress.

The Red-headed Woodpecker is an extraordinary bird for many reasons. This post is already running long so I’ll have to return to this topic at a later date to highlight its unique ecology and relationship with human settlement. Below are two instructive breeding evidence maps from the Ontario Breeding Bird Atlas, which visualize the widespread decline of this species in Southern Ontario. For further intormation, The Birds of North America account (subscription needed) is essential reading for this species but the Cornell account hits some key points too.

1st Atlas (Source: Atlas of the Breeding Birds of Ontario)

2nd Atlas (Source: Atlas of the Breeding Birds of Ontario)

This video was recorded yesterday while revisiting the site where a Louisiana Waterthrush nest was found on May 26, 2010. The stream at this site is flowing with so much vigor that the two waterfalls severely limit the audibility of my playback system. Despite this I was able to locate a territorial male at the south end of the stream complex in a low valley sandwiched between two small ridges. I promptly ended playback as soon as the male responded and watched him for about ten minutes or so as he moved back and forth from the stream to higher perches. At one point he moved higher toward the canopy and was instantly chased off by a bill snapping small passerine, which turned out to be a female Cerulean Warbler (Dendroica cerulea). I followed the female for several minutes and hit an ornithological jackpot of sorts when she flew to a nest located on a horizontal branch of a large Sugar Maple (Acer saccharum), about 15m above the ground.

Cerulean Warblers build their nests high in the upper canopy of deciduous forests that have mature trees, little or no understorey and small gaps or breaks in canopy closure. These characteristics make their nests quite difficult to find and even harder to inspect and monitor! In this case I was able to get a decent view of the nest from either of the two ridges, which put me roughly 15 feet closer to the crown of the large trees growing in the valley. Even with this advantage I still had to zoom to 39x to get a low quality recording. Gotta thank the 749 mosquitoes for all the shakiness. I will definitely be returning to this site (with a tripod!) to monitor both of these important breeders in the next several weeks. Frontenac Provincial Park is one of the most significant protected areas for Canada’s population of Cerulean Warblers now listed as an Endangered species by COSEWIC.

Playback and Bullfrog at the falls

Back to the waterthrush surveys. Things have picked up a bit since my last post but it seems that 2011 will be marked as a down year for breeding Louisiana Waterthrushes in this region. I have not been successful at several reliable sites despite as many as four repeat visits. A review of historical records show some evidence of a downward trend occurring since the first half of the last decade. Despite an apparent population decrease coinciding with the initiation of our study in 2010 it is critical to monitor the sites through the good times and the bad times. Interestingly, the high number of unoccupied sites found this year has only buoyed my interest in the study going forward. Also, the 2011 season is not over yet as surveys at five more sites are yet to be completed and I do have four active sites to keep tabs on.

Ferns and Jack-in-the-Pulpit

Gorge near Birch Lake

Deer Fly season begins

Nesting site along the cliffs across the lake

In this post from early June of last year I wrote about three recently fledged Common Ravens that were found near Clearwater Lake. This is a small but deep oligotrophic lake that is probably best known for its population of Brook Trout. I regularly pass through this area at this time of year and usually notice the clamorous activity of ravens along the lake edge. The noise reminded me to check the cliff for active nests when I passed by last week. It didn’t take long to spot the nest immediately above some rock covered in white wash. The following photos show an adult brooding and three youngsters waiting for food. Unfortunately the photos were taken from a distance of about 100m, which made them pretty grainy but the idea of leaning over the cliff for a better closeup just didn’t appeal.  Common Ravens are regular breeders in the area however this particular record was the first for us since we began in 2009 – very cool!

Incubating adult

Three nestlings

There has been lots of noteworthy observations in recent days but the most significant development continues to be the late arrival of spring and apparent scarcity of Louisiana Waterthrushes in the study area. The mass of ice pictured below was found yesterday near Little Salmon Lake, Frontenac Prov. Park – a late spring indeed. I’ve now surveyed 23 streams and creeks in and around Frontenac Provincial Park with only a few sightings of the target species to show for it. As the above video shows the sites are in excellent condition owing to high precipitation in late winter and early spring. Water levels and flow are higher than a year ago and insect forage is abundant (particularly the black flies!). Click here for a larger version of the clip.

Lingering ice under cedars

Range Map (Cornell Lab of Ornithology)

The Louisiana Waterthrush has a very limited range in Canada. Breeding occurs primarily in Southern Ontario where remnants of mature deciduous and mixed forest remain. Looking at the map above, the small green dot at the east end of Lake Ontario indicates a cluster of breeding sites corresponding to mature woodlands of the Frontenac Arch and Thousand Islands. There is evidence that this species is expanding northward probably in response to maturing and regenerating forest cover since the logging boom of the 1800s. The population in the Frontenac Arch is essentially the northernmost outpost for this species in North America and somewhat disjunctive from the core range. It has been suggested that Ontario’s population is dependent upon immigration from the source population further south and could therefore be subject to more variable rates of fidelity and productivity. Perhaps 2011 will be a down year for our north-wandering pioneers? We still have a few weeks of surveys to complete and will have a much better handle on the situation by early June – I have a good feeling that results will improve.

Little Salmon Lake

The Louisiana Waterthrush recon work took me to a network of streams flowing to and from Little Salmon Lake in the park’s interior. There are some very promising sites in the area but the relatively young age of the forest is probably not suitable for the species at the present time. Regardless of whether the birds are there or not the effort is still worthwhile to describe and index potential breeding locations for the future. This was my first foray into this area, which made for an interesting day. Sandy beaches like the one pictured above are very scarce in the park.

Pickerel Frog on the beach

The only sunbather I found was this Pickerel Frog (Rana palustris) – a nice find. While not exactly rare they are uncommon compared to their close relative, the very similar and more numerous Northern Leopard Frog (Rana pipiens). Pickerel Frogs are always brown in coloration and have squared spots aligned into two neat rows down their backs. The Northern Leopard Frog is usually green, although sometimes brown too, but have circular, more randomly distributed dark markings.