Our fourth consecutive season of Monitoring Avian Productivity & Survivorship (M.A.P.S) is well underway; nearly half finished, actually. We’ve now completed our third of seven visits to each station. As previously discussed results from our first three years of M.A.P.S indicated a sharp, incremental decline in abundance and diversity of terrestrial avifauna in Frontenac woodlands and rock barrens since 2009. The breadth and severity of the decline was foremost in our minds as we walked the trodden paths from usual empty net to empty net in 2011. Hope springs eternal and a new season began in early June 2012. Below is an update on this year’s results to date for Maplewood and Rock Ridge.
First the good news. Numbers of birds are up from last year at MABO, although still considerably lower than in 2009. For comparison, in 2009 we captured 91 birds total through visits 1-3 (72 new/19 rec) while we’ve captured 60 (39 new/21 rec) for the same period in 2012. Very pleased to see that Nashville Warblers and Northern Waterthrushes have returned to the site. We banded a whopping eight Northern Waterthrushes here in 2009 but didn’t even hear or see one a year ago. We’ve banded two adults of each species so far in 2012. Annual totals of Veery and Wood Thrush have been relatively consistent in abundance since 2009 and have returned in expected numbers again this year. Two new species have been recorded for the site; a singing Brown Creeper was detected on June 7 and White-throated Sparrows have been recorded singing on each visit. Notable absentees so far include cuckoos, Hermit Thrush and Field Sparrow.
It’s been a strong year for Yellow-rumped Warblers at MABO. I’ve also observed an unusually high number of adults feeding fledged young in Frontenac Provincial Park this spring/summer – good signs for this northern species in the region. While it’s still too early to judge this M.A.P.S season at MABO, with less than half of the work completed, we are seeing some positive signs of a possible rebound. Weather conditions have been closer to normal during this breeding season than any previous season since our studies began.
American Redstarts are one of the most commonly sampled species at MABO, although they are infrequent nesters within the station boundaries proper. They mainly occupy habitats at the edges of the station but we do manage to capture them later on in the summer when adults and young disperse. In 2009 at least two pairs nested along the shrubby perimeters of small wetlands within the station but they’ve not returned since. Gorgeous bird – one of my favourites.
Rock Ridge (RRID)
While things seem promising at MABO, the same cannot be stated for Rock Ridge (RRID) where numbers are a little down from last season and at least a few species seem to be struggling: most notably Eastern Towhee and Field Sparrow. Both are species of conservation concern due to significant negative trends evident in continental BBS and MAPS data. At our stations these species have consistently decreased in abundance annually since 2009. Urban expansion and changing rural landuse practices seem to be the most commonly suggested causes for the declines in both species, although these issues are less applicable in our region. On the other hand, White-throated Sparrows appear to have rebounded nicely after a near no-show in 2011. Also, the only Pine Warbler that we’ve banded during M.A.P.S was spotted feeding fledged young on June 28, 2012. The bird was originally banded as an immature male on July 18, 2010.
2011 was not a good year for cuckoos. For the first time we failed to capture one during a M.A.P.S season. This Black-billed was a welcome capture on June 18, 2012 at RRID. However, their numbers are clearly down from our first two seasons. This is true for most species at the station – present but substantially fewer in number. Rock Ridge begins to shine in July when birds abandon territories in search of food with their young so it will be interesting to see how the year will pan out at the station.
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.
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!
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.
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.
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.
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.
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.
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.
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.
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….
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.
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.
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.
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.