RESEARCH

SUMMER 2005

This summer MRF is again surveying the southern Ontario population of Short-eared Owls, this time focusing on the Amherst Island / Quinte area which appears to be the last area remaining with any regular concentration of breeding pairs (report to follow).  In addition, MRF Research Director Marcel Gahbauer had the opportunity to survey parts of southern Labrador for Short-eared Owls while conducting more general bird surveys. 

July 15, 2005:
Across much of North America, the Short-eared Owl is a grassland bird, found both in natural fields and to some extent in agricultural lands, especially those managed as hayfields.  Some, however, favour wetlands, and this is the habitat in which they are more frequently found in the north.  The Short-eared Owls breeding in the southern part of the range have declined severely over the past few decades, and habitat loss is presumed to be at least somewhat responsible for that trend.  The number breeding in the far north is thought to have remained more stable, though it is only poorly documented.  Given the known nomadic tendencies of the species and the lack of knowledge about the extent to which individuals move among and between populations, there is also merit in exploring the northern populations in more detail when opportunities arise.  

For a week in early July, I was hired as part of a team to conduct breeding bird surveys in Labrador. The bulk of our work took place in southwestern Labrador, west of Churchill Falls.  Since part of our mandate was to search for raptors, we spent many hours conducting low-level helicopter flights.  The landscape in the area is largely a mix of spruce forest, taiga (predominantly lichen ground cover with scattered small spruce and tundra-acclimated shrubs), fens / string bogs, and lakes.  The fens would seem to offer particularly suitable habitat for Short-eared Owls - a mix of low vegetation and somewhat taller shrubs, large open areas for hunting, and an apparently good prey base in the form of small birds and mammals.  

Despite the apparent availability of habitat, we did not spot any Short-eared Owls.  Of course, since they were not the focus of this study, it is possible that some were present and were missed, as we did not conduct any surveys in the evening or at night.  Nonetheless, it was a disappointing result.  In speaking with other biologists in the region, we learned of at least one small population in a coastal wetland, but the general impression was that it is considered an uncommon bird at best.

SUMMER 2004

To date, MRF's focus has been primarily on the southern Ontario population of Short-eared Owls, for which there is fairly good historical documentation, allowing us to evaluate changes in distribution over time.  However, it is evident that the wintering population far exceeds the breeding population, and it has been speculated that many of these additional birds may come from the Hudson Bay lowlands of northern Ontario.  MRF Research Director Marcel Gahbauer recently had an opportunity to visit that area as part of an Ontario Breeding Bird Atlas survey team, and reports as follows:

June 28, 2004:
For anyone who has never visited northern Ontario, the sheer vastness of the landscape is hard to imagine.  I recently had an opportunity to spend twelve days in Polar Bear Provincial Park, a 24,000 square kilometre wilderness area along the Hudson Bay coast.  The nearest settlement with rail access was Moosonee, nearly 400 kilometres to the southeast; the nearest road was another couple of hundred kilometres further south, at Cochrane.  The roughly two hour flight from Moosonee took us over long stretches of boreal forest, then muskeg, and eventually tundra.  Though only around 55 degrees north latitude, the cold winds coming off the Hudson Bay ice make this the southernmost expanse of tundra in the world - and in terms of climate it is every bit as forbidding as many much more northern locations.

I was visiting Polar Bear Provincial Park as part of a team of three responsible for collecting data for the Ontario Breeding Bird Atlas.  Our task was to cover as much ground as possible on foot, documenting breeding evidence for all species in the area (we ended up surveying roughly 55 square kilometres, walking over 150 kilometres in total).  I selected this particular trip with the expectation that it would give me a good opportunity to observe breeding Short-eared Owls in what is thought to be their Ontario stronghold, and to compare their distribution and behaviour in this area with what we have seen in southern Ontario.

Our base camp was located approximately 12 kilometres south of the Hudson Bay coast, between the Brant River and a large inland lake that was still 90% ice covered upon our arrival on June 15.  The landscape was virtually flat, and aside from the occasional hardy white spruce or tamarack, also treeless.  Visibility therefore was excellent, and larger birds could be seen flying from kilometres away - though it became difficult to identify them at such distances.  

While we never saw the park's namesake, some other mammals were spotted regularly.  Caribou were plentiful, and we observed Arctic Foxes on several occasions.  On the other hand, small mammals were incredibly scarce.  Between the three of us, we spotted a single lemming on this trip, and we never saw any voles or other small rodents at all.  It comes as little surprise then that we saw only one Short-eared Owl.  These birds are known to be highly nomadic, and it is strongly suspected that their movements are tied closely to prey availability.  With small mammals appearing to be at the low point of their natural cycle in this area, the owls are presumably elsewhere this summer.  Interestingly, a good number of Northern Harriers were seen throughout our stay, though we observed successful hunts on very few occasions.

Fortunately, this limited resource did not affect all of the birds in the area.  In total we observed 74 species, for 45 of which we were able to document probable or confirmed evidence of breeding attempts.  However, even for many of them it was a tougher year than usual.  This was apparently the coldest/latest spring in the area in over 30 years, and the cold and wet weather throughout much of our stay was taking its toll, as we found some dead birds, and observed that among the more common species, only a handful of individuals were showing interest in nesting.  A fierce four-day storm with high winds and a mixture of rain, freezing rain, and snow came through toward the end of our stay, and we suspect that it will have reduced the likelihood of successful nesting even further for most species. 

Of course species which come to this area in summer are adapted to harsh conditions, and some year-round residents such as the Willow Ptarmigans were likely able to survive the unusually cold weather without too much trouble.  We suspect that the Short-eared Owls too may have fared alright by moving on to alternate sites early in the season, upon recognizing a shortage of prey in this area.  Whether they have located higher rodent populations elsewhere in enough time to breed successfully this year will remain a mystery for now, but only strengthens our conviction that we need to track the movements of some individual Short-eared Owls to learn more about the timing and direction of their travels.  

The small sample of photos below illustrates the habitat typical of the Hudson Bay lowlands.  If you have any questions about the area, or experiences of your own to share from elsewhere in the arctic, please e-mail me. 

(click on photos to enlarge)

WINTER 2003/04

March 17, 2004:
Kara Kristjanson of the Owl Foundation has reported that she has observed no sign of our test backpack bothering the owl on which we installed it two weeks ago.  She is flying well, and her feathers are covering both the harness and the backpack well.  We will keep the unit in place for a while longer to allow for some longer term observations, but so far we are encouraged that our design appears to be safe.

February 27, 2004:
Today marked our second visit to the Owl Foundation in connection with our Short-eared Owl work.  Kay kept the backpack on the female owl for roughly a month, during which time she reported that the bird seemed largely unaware of it.  Test one passed safely - now we need to know more about how an owl capable of flight handles it.  Fortunately, Kay now has such a female, so we returned this afternoon to put our test backpack on this bird.

Once again, the owl was a pleasure to work with, remaining calm as we secured the harness in place.  The photos below illustrate the design and placement of the harness.  It is important to note that the backpack in use is NOT a real transmitter, nor are actual transmitters this large.  This test unit was intentionally enlarged in all dimensions (as well as in weight) to allow us a better chance of seeing whether it causes stress in any manner whatsoever.  If this owl proves to be entirely unaffected by the test unit, then we can be confident that a slimmer, lighter, and more aerodynamic backpack is unlikely to pose any problems for wild birds.

As with the first test bird two months ago, this owl was quite disinterested in her new backpack, and paid it little attention after we released her back into her cage.  Once again, we look forward to news from the Owl Foundation staff about how she is faring. 

(click on photos to enlarge)

December 28, 2003:
Recently we phoned Kay McKeever, founder and president of the Owl Foundation, in southern Ontario.  The Owl Foundation is widely renowned for both rehabilitation and research, and Kay's decades of intimate work with most North American owl species has made her an important expert to consult on research of any kind.  As it happens, she has long been frustrated by the mystery surrounding the erratic population movements of the Short-eared Owl, and was eager to help us work toward learning more about them.

At any given time, the Owl Foundation is home to roughly 200 owls, housed in an elaborate network of cages that allow the birds to establish their own territories, select their own mates, and generally engage in behaviour as natural as possible within a captive environment.  Many of the birds are permanent residents due to a variety of injuries, but there are also always many short-term visitors which are returned to their point of origin for release once they have recovered fully.

Kay currently has several Short-eared Owls on site, and invited us to visit and have a look at them.  Since satellite telemetry has never yet been attempted with Short-eared Owls, we need to test how they cope with a harness and backpack in a controlled environment before working with wild birds.  While we can pattern our methods after those used successfully on other species, we need to ensure for ourselves (and for the satisfaction of government bodies who regulate research on species at risk) that the design is perfectly safe for Short-eared Owls.  The best way to do that is to equip a captive bird with a mock transmitter and observe its behaviour.  The Owl Foundation, with its full time staff and array of video cameras set up to monitor the birds, is an ideal setting for such a trial, and we are grateful that Kay agreed to help us with it.

Unfortunately, at the moment none of the Short-eared Owls are ideal candidates for such a trial, due to the nature of their injuries.  However, we agreed that as a first step, we would put our trial unit on a female with a permanently damaged left wing.  This won't tell us how well an owl flies while wearing a backpack, but will permit us to monitor how well the harness is accepted, whether the fit is appropriate, and how the behaviour of the bird is affected by it, if at all.

The female Kay selected for us was most cooperative.  Naturally most of the birds at the Owl Foundation have a greater degree of familiarity with people than they would in the wild, but all the same we were pleasantly surprised at how calm she was while we handled her.  The attachment process went smoothly, and before long we were able to put the owl back in a temporary holding chamber, where she could be observed overnight before being returned to her usual enclosure.  She showed little initial interest in the harness or backpack, other than preening a bit of the neoprene under her feathers.  Kay has promised to keep us updated on her behaviour over the weeks to come.

November 25, 2003:
Today preparations began in earnest for the next phase of our Short-eared Owl work - satellite telemetry.  While merely catching the owls for banding has proven to be a considerable challenge, we want to be ready to proceed with the telemetry research as soon as we make progress on that front.

Our plan is to affix transmitters to the owls in backpack fashion, using a soft neoprene harness to provide a sturdy fit while allowing for flexibility.  However, it is critical that such a harness is designed with the proper dimensions such that it fits the bird as well as possible.  We had hoped to take measurements from owls banded during the summer, but since that was not possible we've now found a very acceptable "plan B".

Michel Gosselin, curator of birds at the Canadian Museum of Nature, kindly offered us an opportunity to browse through the bird collection this morning.  We selected a dozen Short-eared Owls, including a mix of male, female, and unknown birds.  For each we carefully measured the neck and chest, then assembled a quick-and-dirty harness from cloth strips that we could use to test for fit.  Of course we realize there's a world of difference between live birds and these specimens, many of which have somewhat unnatural sizes and shapes as a result of how they were prepared.  Nonetheless, this exercise has prepared us well for the next step in the process, which will be testing the harness design on a captive Short-eared Owl.

SUMMER 2003

MRF's primary focus for the summer of 2003 was to survey the southern Ontario Short-eared Owl population to assess the current distribution of breeding birds and describe the habitat they are using (as well as the formerly occupied sites no longer in use).  

Tips on historical nest sites and recent sightings have been provided to MRF by the Ontario Breeding Bird Atlas and the Natural Heritage Information Centre, as well as by individual birders across the province.  Biologists Marcel Gahbauer and Leslie Hunt followed up on these reports to identify currently active Short-eared Owl territories for further monitoring.  Below are some reports on our experiences over the course of our field work.  

Due to the rarity of Short-eared Owls and the fact that much of our work takes place on private property through the cooperation of local landowners, we will not identify any locations precisely in these reports.  However, to provide some context for these observations, we will at least attempt to indicate the general regions in which we are working.

Examples of habitat used by nesting Short-eared Owls:


(click on photos to enlarge)

August 5, 2003:
Our vegetation surveys continue.  As these are daylight activities, we are not surprised that we haven't seen any owls recently.  However, plenty of other birds remain very active.  At a site in far eastern Ontario today, we flushed several flocks of Bobolinks from a field, likely totaling well over 100 individuals.  Most appeared to be juveniles, but there were also some adult females and some moulting adult males among them.  Quite a sight, especially as they erupted one by one from the field, previously unseen.  

At this site we saw an adult Short-eared Owl in flight four weeks ago.  The vegetation in the area it was seen is predominantly bird's foot trefoil, red clover, purple vetch, and grasses (mostly timothy), with patches of sedges and meadowsweet in slightly wetter areas.  For the most part, the species composition of this field is similar to nearby pasture lands, and probably reflects the history of this patch as well.

July 29, 2003:
Summer is rapidly advancing, and over the past couple of weeks we have already noticed the birds becoming much quieter at most sites.  The breeding season is coming to an end for many species, Short-eared Owls included.  As such, our first field season with the owls will also soon be drawing to a close.  All that remains is some supplemental habitat mapping at previously visited sites where we have recorded owl activity this year.  After that, we will spend some time preparing a report summarizing the season's efforts and results; this file will be posted on the website upon completion later this fall. 

July 17, 2003:
This was probably the most exciting night we've had in the field this summer, though it didn't start off too encouragingly.  We arrived unusually early at tonight's location west of Kingston - and were promptly rewarded with a fairly heavy downpour (surprisingly, the second time today that we had been rained upon despite the sky being predominantly clear at the time).  However, our optimism was renewed by the sight of a family of at least five Northern Harriers coursing back and forth over the field we had decided to stake out.  While the two adults were hunting, it appeared that the juveniles were more interested in play, alternately perching on hay bales, and making short low flights between them and the ground. 

Roughly 20 minutes before sunset, the harriers all seemed to disappear.  Presumably they simply settled in the taller grasses around the perimeter of the field, but as on past occasions, we were unable to actually see where they ended up.  If we weren't more focused on keeping an eye open for early-flying Short-eared Owls, we would probably be following the harriers more closely!

It was around 9:45 pm when we heard our first Short-eared Owl in the distance.  Slowly approaching the area where it seemed to be, we heard the calls of at least two different individuals, which sounded like juveniles calling for food.  However, they fell silent again, and it was almost an hour before we had any further activity.  At that point, we saw one of the owls fly across the road, illuminated by the nearby lights - probably the best view of a flight we have had at night.  It found a nearby perch, and then after a few minutes set off hunting again, so we suspect this was likely an adult.  Shortly thereafter, we heard the distinct barking calls again, and realized that at least one of the owls was quite close to us, though we couldn't see it.  As the calls became fainter again, we noticed that at least in part, the vocalizations were being made while in flight.  Clearly the juveniles here have fledged, though by the amount of vocalizing we heard, they are not yet fully independent of their parents.

Our final sighting of the night was one of the owls swooping over an area of taller grass and suddenly dropping down into it, presumably pouncing on prey.  The owl didn't come back up, so it was likely successful - whether it was an adult enjoying a meal of its own, or a juvenile having early success at hunting was impossible to tell in the weak moonlight. 

After having visited several historically active sites where Short-eared Owls appear to be absent this year, a night like this with observations of both adults and juveniles is very encouraging.  It wasn't a perfect night though, as we were unable to catch any of the owls for banding. Whereas wind and rain have been problems for us at other sites, tonight we were up against a very different challenge - a field full of voles!  This made it relatively unlikely that the owls would find our mice before the voles, suggesting that we need to adapt our strategies somewhat before returning here for one more try before the young reach full independence.

July 16, 2003:
There's no doubt summer is quickly moving on - the fireflies and winnowing Wilson's Snipe that were our constant companions in the early part of the season have become scarce sights.  Birdsong around dusk is also noticeably reduced compared to just a couple of weeks ago, though the Green Frogs, Gray Tree Frogs, and occasionally Bullfrogs still keep us company most nights.

Tonight we were back in the Quinte area, doing a follow-up visit at the site where we heard young Short-eared Owls a month ago.  The timing of nesting, hatching, fledging, independence, and dispersal is poorly known for Short-eared Owls in Ontario, and identifying these better is among our goals.  Much of that detail will require monitoring with telemetry, planned for future phases of this project.  However, just by observing active nest sites such as this one we can begin to estimate a rough timeline for southern Ontario.  In this case, we neither saw nor heard any owls tonight in over four hours of monitoring.  Most likely this indicates that the young which were so vocal on our previous visit have become independent, and have either dispersed, or remain present, but are no longer vocally advertising their presence since they have no need to broadcast their location to their parents (and potential predators) anymore.  Of course it's also possible that predators did get them in the interim; that distinction we will be unable to make until we begin to track individuals in detail.

July 12, 2003:
Over the past five days we've visited several more new sites.  Though we did not catch and band any owls on this trip, we made good progress in terms of cataloguing additional sites that they have historically favoured, which will help us in planning the next phases of the Short-eared Owl project.

Our home base for most of the week was the Carden Alvar, a large area east of Lake Simcoe dominated by grasslands and featuring a variety of prairie plants.  Recognized as an Important Bird Area, it is home to significant populations of several birds otherwise uncommon to rare in southern Ontario, including Loggerhead Shrike, Grasshopper Sparrow, Clay-coloured Sparrow, Upland Sandpiper, Sedge Wren, and many more.  While there have been no summer reports of Short-eared Owls here for the past three years, they did occur previously.  The habitat remains unchanged (and apparently suitable), so this presents us with a good opportunity to assess presence/absence with respect to habitat, and to compare this to other sites where Short-eared Owls are still present.

Midweek, we spent a couple of nights setting out our traps at a marsh northwest of Lake Simcoe.  Short-eared Owls had been seen there on a couple of occasions this spring, and apparently bred there in the past too.  After several weeks of working in dry fields, it was a somewhat unusual sensation to be sitting in the midst of a wetland as we monitored our traps!  Not only were the mosquitoes more abundant than usual, but also the nocturnal bird life was much more varied - the Black Terns and Sandhill Cranes argued late into the night, while the Pied-billed Grebes, Marsh Wrens, and Virginia Rails all gave their calls at regular intervals.  At one point the first evening a Great Horned Owl flew past our vantage point, and we also caught glimpses of a couple of more distant birds which could have been Short-eared Owls.  However, it was windy both nights, and we questioned whether the owls would be attracted to our traps if they couldn't hear the mice running around inside.  Whether for that reason or others, we came away empty-handed with respect to the owls - though at least we were able to add several confirmations of breeding to the Ontario Breeding Bird Atlas. 

We wrapped up the week with a daytime survey of a large area of suitable habitat west of Kingston which has supported a significant Short-eared Owl population over the years.  Not surprisingly, the habitat is among the best we have seen, in terms of quality and size.  We observed three families of Northern Harriers, and will return to these sites after dusk to determine whether Short-eared Owls are also present, as is sometimes the case.  

July 6, 2003:
Last night we returned to eastern Ontario to try our luck at trapping in the area we first scouted in early June.  We set up camp at the edge of a field which lies roughly midway between three nest sites which were occupied in 2001.  We faced an unexpected (though not entirely unwelcome) challenge when trying to put up our tents - everywhere we considered, the ground was covered in ripe wild strawberries!  Grazing on those to prevent our tent bottoms from getting stained was a most pleasant delay.

The habitat in this area looks great for Short-eared Owls.  Much of the land is taken up by abandoned fields, dominated by vetch, daisies, clover, bird's foot trefoil, and the aforementioned strawberries.  Scattered across the landscape are several small wetlands, providing enough habitat for the Virginia Rail and Marsh Wrens which kept us company long into the night - and in a much more pleasant manner than the clouds of mosquitoes which also remained with us at all times.  Also nearby are a couple of active pastures with lower vegetation that might also appeal to the owls for hunting. 

The challenge in a place like this is to choose where to put the traps - there is so much suitable habitat for the owls that there is no guarantee they will be hunting in any given area on the nights we are present.  The best we could do was scatter our traps in good-looking spots and hope for the best, then retreat to a central location to wait and monitor.

At some point after midnight, we caught a glimpse of a bird in flight and heard it thud down into the grasses just a few metres away.  A quick investigation showed it to be a Wilson's Snipe - it promptly took off again, but as I followed it with my headlamp to confirm its identity, it swung back around and returned to land almost at my feet!  Over the next couple of hours, it flew off and returned several more times, seemingly unperturbed by our proximity.

Around 3 a.m. we finally pulled in our traps for the night and headed to our tents for some much-needed sleep - little did we know that just a few hours later, the morning sun would be heating our tents like ovens, making further rest impossible!  After a quick breakfast, we explored the area further - and in doing so, caught sight of a Short-eared Owl in flight over an adjacent field, being vigorously chased by half a dozen Red-winged Blackbirds!  Unfortunately, we weren't able to determine where the owl had taken off from, nor where it landed, due to a grove of trees which obstructed our view.  Nevertheless, it looks like we were a bit too far east with our traps, and hopefully returning and shifting our efforts a bit further west will yield better results.

July 3, 2003:
Yesterday night we were south of Ottawa and the rain held off ... but instead we faced a new challenge in that the fields we were trapping at had been either ploughed or hayed since our last visit to them a few days ago.  While we had seen an owl at this location earlier in the season, we never recorded any evidence of breeding.  Over the course of four hours, our traps remained untouched, and while we once had a glimpse of a shape flying past in the distance, it was too dark and distant to tell what it was.  With the change in habitat, it's possible that the owl(s) moved to less disturbed areas.  While the chorus of Green Frogs in the ditches kept us company through the night, the only bird to make itself known was a Sedge Wren which began singing a bit before midnight and kept going for at least a couple of hours - a pleasant surprise, as it is a quite uncommon and local species in eastern Ontario.

June 29, 2003:
Yet again a celestial phenomenon ended up being the highlight of our night.  While setting up our traps around dusk, we began noticing distant flashes of lightning.  However, this was no ordinary lightning - most of it was occurring above the clouds.  As a result, with each flash we saw large patches of cloud illuminated, often painted with the orange and pink colours of the hidden sunset.  Eventually some bolts were visible below the clouds as well, but even then things remained unusual, with many horizontal flashes of lightning, and even one that was distinctly U-shaped.

Unfortunately for us, as fascinating as the lightning was to watch, it also crept steadily closer over time.  Only a bit over an hour after setting out our traps, the rain began pelting down, and with the expectation that the lightning would be soon to follow, we decided to play it safe and pack things in for the night.  In doing so, we came to the somewhat obvious realization that mice walking on wet leaves make nowhere near as much noise as mice walking on dry leaves; consequently the chances of capturing an owl in the rain would likely be much lower (and perhaps it could be expected in general that owls have more difficulty in hunting when it is wet).

June 27, 2003:
Our research team has grown by three members tonight!  Having now identified several active Short-eared Owl territories, we are ready to start trapping the birds for banding.  However, we need some specialized help to accomplish that task ... a trio of mice!  Each will be placed in a separate cage filled with dry leaves and grasses.  As the mice walk around, they should attract the attention of hunting owls.  The cages have been built as bal-chatri traps, lined on top with dozens of monofilament nooses that will gently ensnare the owls as they attempt to land on the mouse (which incidentally is completely safe inside the cage).

Tonight we made our first trapping attempt at a site west of Ottawa where local residents have reported seeing Short-eared Owls this spring.  The mice did their job well, running about in their cages and making themselves heard.  But tonight at least the owls (if present at all) seemed to prefer wild prey.  At one point we heard a squeal that could well have been a just-pounced-upon Meadow Vole, so chances are that a predator of some kind (quite possibly an owl) was in the area at least.

June 25, 2003:
For a warm summer evening in eastern Ontario, tonight was remarkably silent - it seemed at times as if all of nature (except for crickets) was under the force of a giant 'mute button'.  Over the course of a few hours, we heard only a handful of frogs, a far cry from the hordes that were in chorus even just a week ago.  Owls and other nocturnally active birds such as Snipe, Woodcock, Nighthawks, and Whip-poor-wills were entirely silent (or absent, as the case may be - the latter two species in particular seem to be scarce this year wherever we have gone).  In fact, among birds the only species we heard after dark tonight were Swamp Sparrow, Marsh Wren, and Black-billed Cuckoo!

Once again we were without a moon, though the ever-increasing abundance of fireflies seemed to be trying to make up for the lack of light, with some fields constantly flickering with the flashes of hundreds (if not thousands) of them.  However, the unusually quiet night must have been due to other factors.  Most likely, it was at least somewhat due to the lingering warm temperatures from a heat wave in the mid-30s Celsius (mid-90s Fahrenheit) that has enveloped eastern Ontario for the past three days.  A cooler weather system should be arriving within a couple of days, and hopefully with that the odds of finding owls will again improve!

June 22, 2003:
The past couple of nights we have explored some sites south of Arnprior, west of Ottawa.  At one location we had a tantalizing glimpse of a brown and white bird dropping into a clover field, but weren't able to see it again to confirm whether it was in fact a Short-eared Owl.  However, local residents spoke of seeing owls in the area regularly, which gives us hope that we simply had some bad luck on this occasion.  At other sites, we again noticed that rotating agricultural practices have resulted in the suitable habitat being shifted around somewhat.  We heard some of the less common grassland species, such as Vesper Sparrow and Upland Sandpiper, but found no owls at any of these places.

However, our string of interesting celestial observations continues.  Following up on our aurora borealis show last week, we realized last night that (despite clear weather and star-filled skies) we now haven't seen the moon in a full week - no wonder it has been so difficult to spot owls in flight!  Then this evening just before sunset, a meteorite streaked through the sky west of us, a bright green ball disappearing as suddenly as it came into view.

Even the insects are getting into the theme of illumination - over the past week we have seen an incredible number of fireflies at almost all of the sites we have visited.  Last night we came across another interesting insect, a katydid giving its loud grating call long after dark.  Our list of non-avian nocturnal sounds therefore continues to grow - though frogs & dogs remain by far the most common 'auditory interference' we are encountering while trying to pick out the owl calls.

June 19, 2003:
Tonight we returned to the Ottawa area site first visited nearly a month ago.  Persistence - and teamwork - pays off!  While the first visit was a solo effort and yielded nothing, this time two of us split up to cover the area better, and we were rewarded by the sight of a Short-eared Owl actively hunting near the west end of the area.  However, no vocalizations were heard over a span of nearly two hours, so we are left wondering whether the territory might be occupied by a lone bird rather than a family.  Hopefully the silence was due not to lack of young, but to the cold wind either subduing activity, or whistling too loud in our ears to allow us to hear distant owls.  We will try to follow up at this site again in the near future.

June 18, 2003:
Our luck appears to be changing for the better. The past two nights we have been successful at locating Short-eared Owl families in the Quinte and Kingston areas.  In both cases we were unable to see the owls from the roads we were surveying from, but repeatedly heard the food-begging calls of 2-3 young.  Short-eared Owls are known for being able to wander widely on foot before taking flight, and these observations reinforced that fact for us - both nights the cries of different individuals came from locations at least 100 metres apart.  This tendency to disperse over a large area may in fact be why they need to vocalize so regularly, to ensure that their parents know where to deliver food - at any rate it is helpful to us in terms of locating them.

Once again, Bobolinks, Eastern Meadowlarks, Savannah Sparrows, and Wilson's Snipes were among the most common and conspicuous of the birds sharing the habitat of the owls.  At one location we were also lucky to find a family of four Northern Harriers hunting over a large field ... and sure enough, when we returned to the same spot an hour after sunset, two Short-eared Owls were vocalizing at the same site.  Also of note in the Quinte area especially were the large numbers of Eastern Phoebes and Brown Thrashers - the latter walking on the roads more often than not!

Driving home, we were presented with one of the unexpected benefits of late night field work - a nice display of aurora borealis dancing in the sky to the north of us!  The 'show' lasted several minutes, and was a wonderful way to rejuvenate us for the last little bit of the home stretch.

June 14, 2003:
The past five days have seen us covering hundreds of kilometres in southwestern Ontario in the search for additional active Short-eared Owl territories.  Stops along the way have included Nobleton, Caledon, Orangeville, Shelburne, Grand Valley, Stoney Creek, Binbrook, Hagersville, Selkirk, and Wainfleet - plus Burlington, to pick up some supplies from our research partners at the Canadian Wildlife Service.

Once again, we found a fair amount of suitable habitat - not always exactly at the sites where Short-eared Owls have nested in the past, due to rotating land use patterns, but usually in the same general area.  However, as suitable as it seems to our eyes, the owls seem to feel otherwise - night after night we have come away from apparently good sites without seeing or hearing any of them.

We have also spent a fair amount of time at each site during the day - not so much looking for evidence of Short-eared Owl presence, but assessing the habitat and checking for other indicator species.  In particular we have been on the lookout for Northern Harriers, which over much of North America share habitat with Short-eared Owls and are in a sense their diurnal counterpart.  To our dismay, we have only found a single male harrier over the past week, which seems like a bad omen for the owls, given that in general the harrier remains a considerably more widespread species in Ontario.

And then there are all of the frogs, which at times threaten to drown out any possible owl calls - the Gray Treefrogs have been particularly loud at some sites, but we have also encountered most of the other common species - Spring Peeper, Green Frog, Eastern Chorus Frog, Bullfrog, Leopard Frog, and Bullfrog.  A pleasure to listen to under normal circumstances, but remarkably frustrating when straining to hear faint owl cries in the distance!

Short-eared Owls are believed to be at least somewhat nomadic in their breeding habits, adjusting their distribution in accordance with prey abundance and/or other factors.  Based on our observations this week, it appears that southwestern Ontario is not attractive to them this year, and we will likely focus our remaining efforts more on eastern Ontario as a result.  That being said, chances are that at least a few owls remain somewhere within southwestern Ontario, and we would be happy to hear from anyone who might know of currently active sites - please e-mail us if you do have any sightings from this spring / summer.

June 4, 2003:
The Short-eared Owl field season is officially underway for us!  Over the past couple of days we have scouted a series of sites in eastern Ontario where Short-eared Owls were recorded by Ontario Breeding Bird Atlas volunteers in 2001 and 2002.  The area is largely agricultural, and land use has changed at a couple of sites, but overall a considerable area of suitable habitat remains available.

Despite this, local observers have told us that sightings so far this year have been few and far between, and our experience reflected that.  Of all the sites we visited, we were able to confirm the presence of Short-eared Owls at only one of them.  However, it's a start, and hopefully several other sites will follow shortly.

May 22, 2003:
A preliminary visit tonight to a historically occupied Short-eared Owl territory near Ottawa was unproductive - though many other birds were abundant (not to mention frogs), I didn't hear or see any owls either before or after sunset.  We will begin a more systematic survey of previously occupied territories in early June.

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