Birds of Chatham-Kent, Then and Now, Part IV

 

Great Black-backed Gull

Then: it was not considered hypothetical, but Wood had only seen this species on one occasion, and made no reference to it any earlier.

Now: Clearly things have changed. Great Black-backed Gull was considered mainly a north Atlantic region species, but over the years, the species found at least the lower Great Lakes to its liking. It was first recorded on the Blenheim/Rondeau CBC in 1948. Beginning in 1965 it has been seen on every count, with typically up to a dozen or so recorded during the first couple of decades following. The numbers kept increasing, but fluctuated greatly depending on the seasonal weather and the conditions of the day. The maximum number recorded on this CBC was 380, in 1991.

This species is a 4-cycle one, meaning it doesn't attain full adult plumage and breeding until its fourth year. Therefore sub-adults can be found in C-K almost any time of the year, especially if there is some open water. The two photos above show a full adult first, with a sub-adult, likely a first winter bird, below. Both photos were taken in the Jan/Feb period.

Herring Gull

Herring Gull nest, 1987

Then: Herring Gull was considered a common transient and winter visitor, with numbers of non-breeding birds remaining in the summer. Even during the early winter, when numbers were most commonly recorded for the CBC, the maximum number was about 200 in 1939.

Now: Herring Gull is a large, fairly aggressive gull, eagerly defending its food against even other members of its kind, as the first photo shows. The numbers have increased considerably since the writing of Wood's manuscript. Since the early 1960s, seldom are there less than 100 birds recorded on a Christmas Bird Count, and typically there are several hundred. In the last 15 years, the numbers have averaged almost 900 birds, with as many as 3779 recorded in 2008. One of the reasons for this increase may be due to the presence of Ontario's largest landfill just a short flight away.

Herring Gull has become an occasional breeding species as well. When the water levels of Lake Erie are such that the south beach of Rondeau is a good breeding site, gulls can occupy parts of it, as the above photos show. The middle two photos were taken in June, 1987, while the fourth photo was taken in May, 2013. The latter one wasn't on the south beach, but was taken from my kayak while I was exploring some of the exposed small islands at the south end of the marsh.

Ring-billed Gull

Then: Ring-billed Gull was considered a common spring and fall transient and a summer and winter visitor. Up to 30 birds were reported periodically in spring and fall, with late fall being the time when the largest numbers were recorded. Up to 75 birds were recorded for the first few Christmas Bird Counts.

Now: as with the previous two gull species, the numbers have changed considerably. It is typically the most abundant gull species most of the year. The same CBC in the last 25 years has averaged over 3300 birds, with a high of 12510 recorded in 2001. One of the reasons for this increase may be attributed to Ontario's largest landfill just a short flight away.

When conditions are suitable along the south beach of Rondeau as a nesting site, they will use it as the above photos show. The first and third photos were taken in July, 1983, while the middle photo was taken in June, 1987. 

Forster's Tern

Then: Forster's Tern was considered to be formerly a common summer resident at the St. Clair flats, but at the time of writing (1945), a very rare visitant. There was only one record for this species at Rondeau, that being May 13, 1946.

Now: It is a regular, but not abundant migrant present in spring, summer and autumn. When the marsh water levels are suitable, it has been known to nest, with the first known nesting occurring in about 1980. The nesting photo above was taken in July, 1981. Forster's Tern is generally considered a mid-western species, but with some local habitats in the vicinity of Lake St. Clair showing similarity to the tallgrass prairies and wetlands of the mid-west, this species and others have been known to occur and breed in C-K with some regularity. With Rondeau being a bit farther east, such mid-western species are generally less common either as migrants or breeders.

Common Tern

Then: Common Tern was considered a common summer resident, breeding in colonies on a sand spit in the McGeachy Pond area near Erieau, as well as being fairly abundant in the marshes along Lake St. Clair. Flocks of two hundred were seen foraging along the water. However in several cases some of the eggs have been lost to Herring Gulls, Bonaparte's Gulls and skunks.

Now: While Common Tern is quite regular and sometimes fairly abundant in Chatham-Kent, nesting has diminished substantially. I have seen an occasional nesting attempt along the south beach of Rondeau a few decades ago, but no one has reported them nesting anywhere in recent years. There were no confirmed breeding records in C-K in either of the first two OBBAs, although they did rank as 'Probable' in two squares at Rondeau. The changes are likely the result of three things: (a) a large increase in gulls, which are predatory; (b) the higher water levels of Lake Erie, making nesting sites less available; (c) the increased usage of boaters illegally using the south beach, causing disturbances.

Black Tern

Then: Black Tern was considered a common summer resident, breeding in all the large marshes of the county. An average of about eighty birds were reported at Bradley's marsh in the early part of last century, and was considered more abundant than Common Tern.

Now: In the Rondeau/Erieau area it is regular, but not common at any time. The two photos showing Black Tern nesting were taken in the late 1970s and very early 1980s. The upper one was taken at McGeachy Pond; the lower one was taken at the south end of Rondeau. The water levels at McGeachy Pond used to naturally fluctuate, allowing for functional habitat, but about thirty years ago, a water control system was put in, so the habitat has declined. 

In some of the larger marshes along Lake St. Clair, it is more common, but certainly not abundant. Eighty birds would be a huge increase nowadays! During the second OBBA, there were 5 squares in C-K that had this species 'Confirmed' breeding. There are likely several reasons for the overall decline: (a) high water levels thus reducing cattail habitat; (b) a huge increase in the extent of highly invasive Phragmites, choking out some of the high quality habitat Black Terns prefer; (c) some relatively minor loss of habitat due to farming.

American Barn Owl

Then:  The American Barn Owl was considered a permanent resident, and the first Ontario nesting record was at Charing Cross. Wood goes on to give details of other records of them nesting, being shot, or being observed, at many locales in C-K.

Now: a very scarce, very occasional resident. I have seen it on a couple of occasions, once at Shrewsbury in 1973 and near St. Clair NWA a few years ago where one was seen periodically by various people over the course of about three years (2006-2008). We managed to get it on the St. Clair NWA CBC those three years. I do not have any photos, other than in my memory. In spite of searches, its roosting spot was never determined. There have been a few other records in C-K over the years, but details have been kept quite secret due to the potential disturbance by numerous birders who would descend on them in order to add the species to their life list.

Snowy Owl

Then: Considered an irregular winter visitant, but the numbers fluctuate. Even as recent as in the first part of last century, birds of various species were shot for the taxidermy trade, or whatever, and this owl species was a common target. Wood goes on to say that the winter of 1945-46 was the heaviest visitation in recent years, and " Twenty birds were definitely known to have been shot in the vicinity of Chatham and hunters told of many others killed and left in the fields." An unfortunate entry.

Now: up until recently the species was still considered an irregular winter visitor due to the cycle of breeding success, which in itself, was based on the population of lemmings and other rodents available to them during the nesting season. Abundance of food was a critical factor in the courtship display and therefore nesting activity and success. When larger numbers of young were raised, more would migrate south to survive the winter. Those cycles continued, more or less, up until 2010, where for the St. Clair NWA CBC, 1-3 birds would be seen in successive years, and then missing them for one or two years. However beginning in 2011, Snowy Owls have been seen each year, with sometimes a dozen or more birds being counted. The 2022 CBC had an incredible all time high of at least 23 owls recorded. The Blenheim/Rondeau count has shown a similar trend, although overall in smaller numbers except for an amazing 26 birds reported in 2014. This trend begs the question of what changes occurred in their breeding territory to presumably make their food source more readily available.

Short-eared Owl

Then: This species was described as an irregular winter visitant and very rare summer resident. However there were some incredible numbers given for them at times, as about 50 were reported at St. Luke's Marsh (immediately to the north of SCNWA) in March of 1940, and in January of 1943, there were about 100 birds reported there! There was only one confirmed nesting record known at the time, in June 1944, in a large pasture in the former Raleigh Township.

Now: While Short-eared Owls continue to appear in late fall, through the winter and into early spring, it is rare to see even one bird without a lot of effort during those times. Clearly their numbers elsewhere have fallen off so that there are few to appear in C-K during these non-breeding seasons. Getting 1-3 birds is at best, the norm for CBCs in the area, and in some years one does not get them at all. There have been some blips in these numbers, as an amazing 24 were tallied on the Blenheim/Rondeau CBC in 2010.

There is breeding habitat present, especially in the vicinity of the larger marsh complexes associated with Lake St. Clair. The amount of pasture or hayfield habitat elsewhere in C-K has declined in the last few decades, although some remains. However there have been no breeding records at any level for either of the first two OBBAs.

Chuck-will's-widow

Then: considered hypothetical, based on a single encounter in a woodlot in the former Raleigh Twp in 1920.

Now: Currently a very rare species, although in the late 1970s and early 1980s, it was heard and seen annually at Rondeau. Indeed on one occasion there were up to 7 birds calling at various places along Harrison Trail both north and south of the Visitor Centre. It is believed that at least some of those birds were the progeny of the previous year or two. However in spite of efforts to try and locate any nesting evidence, this very cryptic species was never confirmed. There have been occasional records since that time, but very rarely, and almost entirely in May/June.

Whip-poor-will

Then: Considered as a common spring and fall transient and a rare summer resident.

Now: It is a regular spring migrant, but never common. A few can be heard under the right circumstances at Rondeau, for a couple of weeks in late May/early June. On occasion one or more will continue well into the breeding season, as they can be heard from the wooded ridges east of the Marsh Trail as well as along Harrison Trail. No doubt some have attempted to nest, perhaps successfully, although confirming this crepuscular creature would be difficult. The above photo was taken on Nov 4, 2012, of a bird high up in a White Pine along the South Point Trail. It is late in the season for an insect eating bird!
  

Common Nighthawk

Spring migrant

Autumn migrant

Then: it was considered an abundant summer resident, commonly nesting on flat, tarred and graveled roofs in cities and towns.

Now: while it is a regularly occurring species, it is anything but abundant. The open pine forests they breed in farther north are not available to them in C-K, so any attempts at breeding would still require the flat, tarred and graveled roofs. One used to be able to detect their 'boom' in the evening in cities and towns but not recently. Undoubtedly a few spring arrivals remain to at least attempt to nest. There were several atlas squares in both of the first two OBBAs recording them up to the 'Probable' level, but no 'Confirmed' records. Common Nighthawks are typically a bit more common in the autumn as they migrate southward from more productive breeding grounds.

 

Birds of Chatham-Kent, Then and Now, will continue in a future post.

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