Natural Areas of Chatham-Kent, Part 10 (Blenheim Sewage Lagoons)

Okay so the idea of a sewage lagoon maybe doesn't sound like much of a natural area. But wildlife have a different perspective, and therefore a complex of sewage lagoons is very much a magnet for wildlife.

If anyone has been out in the prairie pothole region of North America, you may realize that potholes filled with water are common place. Certain types of wildlife in particular are attracted to these potholes. So to wildlife passing through Chatham-Kent, and other areas where sewage lagoons are present, this concentration of 'potholes' filled with water are ideal places to visit, and in some cases nest at. As a result, some species historically found much farther west, have expanded their range to include sewage lagoons in southern Ontario.

These lagoons are easy to find for humans, as well. This particular set is located just west of Blenheim and north of Hwy 3/Talbot Trail on, appropriately named, Lagoon Road.

There is a condition for visiting, however, and that is an annual permit which is required to ensure not just anyone goes in and to protect the municipality from liability. The permit system has been in place for these lagoons since the mid 1980s, and is available from the municipal centre in Blenheim, located next to the post office.

To date there have been ~235 species of birds recorded here. What is so attractive to wildlife? I'm glad you asked.

Water birds, especially ducks, need places where they can rest safely from terrestrial predators.

Ducks, herons and shorebirds can feed on the abundant aquatic life, including invertebrates, fish, frogs, etc.

Shorebirds of various types are abundant especially during the spring and fall, including the Spotted Sandpiper shown above and Lesser Yellowlegs shown below.

Sometimes shorebirds can be extremely abundant.

Others are regular, but less common.

Short-billed Dowitcher

Long-billed Dowitcher

Wilson's Phalarope

 Wilson's Phalarope is really a species of the prairie pothole region, which has nested at these sewage lagoons on occasion. In the photo of them below, in their breeding plumage, it is the female that is the more brightly coloured, as it is the male that does most of the incubating.

Still other shorebird species are unusual, and if they occur immediately attract interest from other keen birders.

American Avocet

Buff-breasted Sandpiper

Marbled Godwit

Species of ducks that are more typical of the mid-western regions are more common place now, and include the following two species, both of which have attempted to breed here:

Northern Shoveler

Ruddy Duck

The next species, Greater White-fronted Goose, does not breed, but is sometimes seen on migration.

 It is sometimes called speckle-belly, due to the pattern of its belly shown here.

The waters of a sewage lagoon are nutrient rich, as one might expect, and this means aquatic insects are abundant. Land birds such as swallows benefit immensely from insect hatches. This is most evident during periods of cool weather when insects might not be available over the land, but with the warmer water retaining heat and with multitudes of insects hatching and becoming air borne, swallows can feed over these ponds to sustain themselves at a critical time. If one wants to see this, visit the lagoons during a cold spell. For example during a cold spell in mid-May of 2017 when the temperatures dropped close to freezing, there were thousands of swallows swooping over the water feeding, or resting on the berms separating the ponds.

 Tree Swallows were the most abundant, but Cliff Swallows and others were present in larger than usual numbers.

Cliff Swallow

Cliff Swallow

Tree Swallow

The shrubs surrounding the lagoon complex can be a great spot for land birds, especially on migration.

Rusty Blackbird

With such concentrations of birds, raptors that feed on birds such as Peregrine Falcon, are periodically attracted to the site.

Other species of wildlife are found, as well, with some being rare.....

Cattle Egret

 ...some uncommon....

Short-eared Owl

....and some not so rare.

Groundhog

The very openness of the lagoon complex and with it being so accessible to birders due to the berms surrounding the ponds, make it a great spot for birders. Having said that, since it is easy for humans to see wildlife, keep in mind that wildlife, which have great vision and survival instincts, can see humans even better and may be difficult to approach. Binoculars are a must, and a scope is highly recommended.

With all of the openness, there are lots of wildflowers present around the edges, making it a great spot for butterflies as well. It is a regular stopping point for us in our annual Butterfly Count in mid July, but it is sometimes better in the late summer when plants such as New England Aster, which is a favourite nectaring plant for butterflies, are abundant. The first three species are common here, as are others.

Clouded Sulphur

Common Ringlet

Orange Sulphur

 The next two species are rare and irregularly found here in spite of their names.

Common Buckeye

Common Checkered-skipper

All in all, sewage lagoons are a great place to find wildlife......you may be surprised!

Hot and cold birding

Late last week and on the weekend brought some really up and down weather. The first couple of days were quite pleasant....warm and if you were in the sun and out of the wind, even hot at times. There were some new migrants appearing on the landscape. Rose-breasted Grosbeaks were widespread.

 Eastern Kingbirds were also fairly plentiful.

Northern Parulas were more abundant than anytime I have seen in the past. It used to be that getting a few in a season was considered good, and even at that, one seldom had more than one or two in a day. On these days there must have been a fallout of a large number of migrating parulas, as it was not uncommon to see 8 or more in a single day, with as many as 19 being reported by a single observer.

Northern Parula

 Blue-winged Warblers are always a good find, although they aren't always easy to photograph as they skulk around the leaves and ground vegetation.

Blue-winged Warbler

 At least a couple of male Hooded Warblers were reported, and I caught up with one of them.....skulking around in the lowest shrubby levels, of course, making the auto-focus of the camera impossible to use. Manual focus on a quickly moving bird is not easy! Most of the shots were deleted.

The relative warmth was also good for reptiles. This Eastern Garter Snake was enjoying a sheltered spot with good exposure to the sun.

 Within about a metre of the South Point Trail was this beautiful Eastern Fox Snake, an endangered species here in the southwest. It had probably been there for quite awhile, hours even, while hundreds of birders went on by searching for warblers. The sharp eyes of Denise D discovered this critter and got my attention just as I was about to exit the trail. Even though it was partly curled up, we estimated its length to be well over a metre.

Shortly after photographing this latter snake and then leaving the South Point Trail parking lot, I looked out towards the lake shore and saw someone at the edge of the dunes. I looked at them through binoculars and she looked right back at me through her binoculars....it was Tianna, and she was waving me over. An hour or so earlier we had been alerted by Steve C of 6 Whimbrel out along the beach and had gone over to investigate. Even though it was only 15 minutes later, the birds had left. But apparently they had not gone far. Tianna had re-located them! A slow and careful approach, and using a good telephoto lens, resulted in this following image.

Whimbrel pass through the lower Great Lakes in a relatively narrow window of time, and these were the first ones reported not only for Rondeau, but for the entirety of the Ontario side of the lower Great Lakes as far as I am aware. Unfortunately they did not stay around for a lot of others to view.

Other water birds had recently arrived in good numbers, including many Common Terns. At least 500 were noted at the Erieau harbour area, and a similar number were seen a day or so later along the east beach of Rondeau.

Some of the ~500 Common Terns

This next bird isn't a recent arrival, or even an uncommon bird, unfortunately. However this close-up shows why it is called a Double-crested Cormorant as the two feather tufts are quite visible here.

The weekend arrived, and as predicted, the weather deteriorated in a big way. Colder temperatures, strong winds and rain. The only good thing one could say about it was that the birds were staying low and easier to see. There was little or no bird song.....I think the only sound they were making was their beaks chattering!

Birds were fluffed up to provide a bit more insulation from the cold.

Fluffed up Song Sparrow

Fluffed up Swamp Sparrow

The Wood Thrush in this next photo was totally exhausted, sitting in the grass by the picnic area, allowing a very close approach. I'm not sure whether it was the cold or the exhausting flight or both.

And then it snowed. In mid-May! Snow and ice pellets came down quite heavily on a couple of occasions, but fortunately not for long. It isn't the first time ever and it likely won't be the last, but the birds were not enjoying it. Nesting birds refused to leave the nest, not wanting the developing embryos or recently hatched young to suffer from the cold.

The Blenheim Sewage Lagoons was a busy place, and you know it is windy when there are white-caps on the water there! Wind speeds were reported to be in the 30-45 km/hr range, so it wasn't surprising to see the white-caps.

There was a huge number of swallows there. I estimated there to be at least 1500 of them swooping low over the water, over the pathways and over the grassy areas, hoping for an insect or two to help sustain them. Many were just resting on the ground or on a low branch.

Tree Swallows were by far the most abundant, with an estimate 1000 or more.

Tree Swallow

Bank Swallow

Barn Swallow

Cliff Swallows were fairly abundant....I don't recall ever using that term to describe Cliff Swallows here before! At one point I could see at least 35 in a narrow strip. There could have been well over a hundred altogether.

Cliff Swallows

Fluffed up Cliff Swallow

The water temperature was warmer than the air temperature, by a considerable margin, I expect. I am not sure what insects were hatching, but the swallows were at least trying for any insects that were emerging.

I have often wondered about the health of birds that feed on insects emerging from sewage ponds. The insects are abundant in such waters, but what chemicals are concentrated in their systems, which will only accumulate to a potentially serious level in any bird that feeds on them? After all, the water is cleaned somewhat from the organic material that is flushed or otherwise gets into the system, but what about all the chemicals that come from potent pharmaceutical materials, prescription drugs, etc, that are also flushed into the water system but aren't removed? Some of that will be absorbed by the insects living in these sewage ponds and passed on to any insect eating birds and bats.....it can't be a good thing!

Shorebirds weren't busy feeding...they were taking refuge from the bitter cold!

This Turkey Vulture was feeding on the remains of a Raccoon. Presumably the Raccoon had neglected to sign up for lessons from the local chickens on how to cross the road successfully :-).

Fortunately the cold only lasted for a couple of days, but I am sure that it seemed a lot longer than that for some of the birds that had to endure it.