Wednesday 20 December 2023

Christmas Bird Count Weekend 2023

Been awhile since I've written about, well, anything—let alone a Christmas Bird Count (CBC). Each year for the past several years, I have participated on both the London CBC and the Rondeau/Blenheim CBC, which fall in that order on the same weekend (first weekend of count period). It is always a fun time spending the whole weekend counting birds! For a long time, these were also the only CBCs that I did, however I have since taken on the Bayfield and the Algonquin CBC, which will be taking place next week. 

I didn't really take my camera out much, so I will have to dig into the archives for supplementary photos... 

I started my London CBC route (which runs alongside the Thames River in Southeast London) around the same time as I usually do. The weather was rather mild, there was little wind, and no rain! Overall, seemed to be a nice day weather-wise to be out! The mild weather likely doesn't help when it comes to concentrating birds, although there is potential for some odd lingering species. 

 Right out of the gate, many of the usual suspects, such as Mourning Doves, Northern Cardinals, American Tree Sparrows, and Dark-eyed Juncos. A couple Winter Wrens were heard chattering along the river. A Great Blue Heron also flew by, which is a very hit and miss species during the winter along the river, although not too unexpected. 

Continuing along, we found a nice little group of birds, and upon pishing them in, had four species of woodpecker, including a Yellow-bellied Sapsucker, a very good bird for the CBC. I know at least one other was seen on the count.
We encountered a couple more groups of songbirds along the way, but generally, it was pretty quiet. I found there to be good numbers of Song Sparrows (I ended up with 14), goldfinches, chickadees. A total of 20 Downy Woodpeckers was impressive as well. 

Song Sparrow

I had a total of 36 species along my route that morning, and just shy of 600 individuals. This ties my highest species count for this route, but it in the bottom half for number of individuals. This isn't too surprising, however, as the duck numbers that usually pad the individual totals just weren't present this year. I did add a few new species to the all time list for this route as well: Yellow-bellied Sapsucker, Brown-headed Cowbird, and Sharp-shinned Hawk. I have had some goodies on this route over the years such as House Wren (2019), Lincoln's Sparrow (2022), and Yellow-rumped Warbler (2018).

 After completing my route, I went over to Pottersburg Park to search for a couple lingering species. Of course, a species of priority for count day was the overwintering Philadelphia Vireo that was found there. This bird represents the first winter record of this species in Ontario. Luckily, it had been seen earlier in the day by another party—of course this is a new record for the London CBC, and likely all Canadian CBCs. I did put in a little time trying to see it anyways, but had no luck. I succeeded on other fronts though, with seeing a wintering Hermit Thrush (one of several seen on the CBC), as well as a Ruby-crowned Kinglet. 

Philadelphia Vireo (from December 14)

I'm not sure what kind of totals are out there for the London CBC yet, but I do know that a number of good birds were seen, including another count first, the Black-billed Magpie that had been around for a couple weeks just south of London. 

The next day it was down to Rondeau, arriving just before sunrise. Unfortunately, the weather was not as nice as the day previous. Although it was actually a bit more mild, it was raining pretty steadily, and wasn't about to let up. It was difficult to want to get out of the car. Eventually, I did, and started the lakewatch at the visitor centre beach access, as per usual. It was slow at first, but the winds were good, so I persisted. Soon the birds were moving, and there were things to look at. Normally I might lakewatch for an hour before starting my walking, but things were still going strong, so I ended up being out there for nearly three! Red-breasted Mergansers were really moving, and I tallied over 3000, as well as a number of scaup and Common Goldeneye. There were a few White-winged Scoters, as well as a pair of Surf Scoters. Another highlight were some Red-throated Loons. Although not really moving, there were also quite the number of Ruddy Ducks. I estimated over 1000, but surely many more than that. Very difficult to count in the waves.

Red-breasted Mergansers

After I finally pried myself away from the lake, I starting walking up Lakeshore Road towards the campground. It was generally pretty quiet, but with a few pockets of activity. Highlights included several White-throated Sparrows, a pair of Tufted Titmouses (titmice? who knows), and a couple Hermit Thrushes. I ended up seeing four Hermit Thrushes on my walk, so it seems to be a good year for them. 

Hermit Thrush

At the churches in the campground there was a large sparrow flock, mostly tree sparrows and juncos, but also a couple of Field Sparrows, which were nice to see. A Hermit Thrush here too, but not too much else to speak of, other than a Red-tailed Hawk. 

It was then back south down Harrison Trail, but not before poking around the Pony Barn a little bit. I did hear a Pileated Woodpecker here, which may prove to have been the only one on the count! 

Harrison was...quiet. But I mean, it usually is. My highlights were that fourth Hermit Thrush, a robin, and the screech owl in its usual spot along Bennett Ave. 

I ended the route, much later than I usually do, back on the beach. I was hoping for a Bald Eagle, but no luck. I don't think I have ever missed that species before! Perhaps the rain in the morning had kept them at bay.

I was losing sunlight, but just for fun, poked around the north end of the campground a bit. I missed the Audubon's Warbler, but saw some of the other "Myrtle" Yellow-rumped Warblers. Also a couple of Fox Sparrows. Golden-crowned Kinglets were also around, taunting me, as I had missed them in the 10km+ of walking I did!

Lastly I checked Keith McLean CA on my way out. Sometimes there are some interesting things trying to overwinter here. On past CBCs I have seen Killdeer, Least Sandpiper, and Nelson's Sparrow. Not today however! Only things of note were Savannah Sparrows, a flicker, and a Sharp-shinned Hawk.

Another "CBC Weekend" in the books! I am looking forward to the Bayfield count on the 27th! 

Tuesday 10 October 2023

Southern Lake Huron Lakewatching: Thanksgiving 2023

Not really a post to tell much of a story or anything, but just wanted to gather some interesting observations and put them out there. This past weekend (Canadian Thanksgiving) saw some excellent conditions for lakewatching on Lake Huron, with a cold front moving through starting on Friday (and really taking off starting Saturday), as well as a pressure system moving through, giving us a break in the southerly winds, with things switching around to being more northerly. With the pressure system/cold front moving in from western Canada, the winds were from the western direction. Optimal conditions.

I spent three mornings (October 7, 8, and 9) at The Bluff, a location north of Grand Bend in Huron County, Ontario. This location gives an excellent vantage point to watch the lake. I started each morning around 0730-0800h, and usually stuck around for a few hours. Interestingly, a few other parties also did lakewatches on Lake Huron, which allowed for interesting comparisons between the different locations. I want to compile these lists here, and give a brief synopsis of each day. 

First, a map of each of the lakewatch locations along southern Lake Huron, which I am defining as Lambton and Huron Counties.

As the jaeger flies (neglecting air resistance, which jaegers laugh at), approximate distances from The Bluff (Huron County) are as follows:

Waterworks Road (Huron County): 5km

Grand Bend Beach (Lambton County): 8km

Ipperwash Beach (Lambton County): 28km

Kettle Point (Lambton County): 30km

Unfortunately, I don't believe any observations were undertaken in Sarnia, nor can I find anything from the southern end of the lake in Michigan. 

Saturday: October 7, 2023

Weather comments (from my eBird checklist): Strong WSW winds, rain starting overnight but ceasing by 0800h. Variable cloud cover, with some extended periods of sun. 8-12°C.

Radar from Environment Canada Exeter station:

October 7, 2023 00:00 EDT

October 7, 2023 08:00 EDT

Hourly wind speeds from Environment Canada:

Goderich, ON

Sarnia, ON

This day was the first day of decent westerly winds in awhile, and came right after a cold front. As expected, there was a bit of movement, although I think it didn't quite live up to my expectations, personally. Perhaps it is too early in the season for large numbers of ducks and things. Nevertheless, an enjoyable day, and the conditions for birding were nice, even with the strong winds. 

eBird checklist from The Bluff:

Two other spots were lakewatched from this day. Grand Bend Beach, just 8km or so to the south had a similar day, although with higher numbers of ducks of some species, and lower numbers for other species. A common theme amongst the days was that other lakewatch locations had lower scoter numbers than we had at The Bluff, which I found to be interesting. Also, on this day, Peregrine Falcon numbers were much lower at Grand Bend Beach than we had at The Bluff, which is noteworthy. On a fun note, some of the same individual birds were seen at both lakewatches! 

Grand Bend Beach:

Kettle Point was also surveyed. Nearly twice the number of ducks were seen, as well as a couple of jaegers. Of course, the big difference in the number of Bonaparte's Gulls and terns is also of note. 

Kettle Point:

Sunday: October 8, 2023

Weather comments (from my eBird checklist): Rather strong NNW winds, gusts to 60kph. Heavy rains overnight, but ceased by 0800h (much like yesterday), and didn't really rain again aside from a few rain drops here and there. The big rain system seemed to move SE just directly north of us. Actually cleared up and got sunny with blue skies for a bit, before returning to overcast by end of observation period. Light rain starting just as we left. Cool temps 7-10°C. Not that uncomfortable to bird in actually, but wind made viewing difficult.

Radar from Environment Canada Exeter station:

October 8, 2023 00:00 EDT

October 8, 2023 08:00 EDT

Hourly wind speeds from Environment Canada:

Goderich, ON

Sarnia, ON

This was the day I was most excited for this weekend. The forecasted rain actually missed us, so we had fairly pleasant conditions for viewing on this strong NW wind day. Fewer ducks moving today, but it was made up for with some pelagic birds. At The Bluff, we had a few jaegers, and other lakewatches had some as well. Notably, scoter numbers were up, with a few hundred at The Bluff, mostly Surf, but also a number of White-winged. 

Grand Bend Beach had a great day, and despite the somewhat small distance between The Bluff and there, it was quite different. You can actually see the one point from the other point! A few more jaegers, although less ducks. More gulls, and notably a couple of Sabine's Gulls (which hurts a bit, not going to lie!). I feel confident that these birds didn't go by us unnoticed as we were quite diligent scanning the while time, so they likely came from further out in the lake in towards land around Grand Bend (??).

Ipperwash Beach was surveyed on this day. Again, they had more gulls and jaegers, but less ducks. Notably, both Parasitic Jaegers and Long-tailed Jaegers were seen, as well as a Sabine's Gull.

Notably, while not in Southern Lake Huron, a lakewatch was undertaken in Kincardine (Bruce County). Lots of differences, which isn't unexpected given the distance (~89km).

Monday: October 9, 2023

Weather comments (from my eBird checklist): Strong WSW wind, initially more W (with perhaps a slightly N component), and switching a bit over course of observation period. Clear, no precipitation, cc 80-100%. 8-9°C. Clear overnight (the first clear night in a few days).

Radar from Environment Canada Exeter station:

October 9, 2023 00:00 EDT

October 9, 2023 08:00 EDT

Hourly wind speeds from Environment Canada:

Goderich, ON

Sarnia, ON

Not a whole lot to say for this day. With winds swinging back towards the south, it was expected that things would be slower, but it turned out to be much slower. In the first half hour of observation, I had seen five individual ducks, and it didn't pick up much more after that. In general, just a lot fewer of everything. Why is that? Hard to say. Could the south winds be causing things not to move as they would on a north wind? Were the winds too strong? My personal theory is that since it was the first clear night (in this region) after the advance of the cold front, that the lake "cleared out" and many of the birds that had been on the lake the last couple of days left. I just don't think it would make sense for all the same birds to still be there, and we don't see them. Most notable is the drastic decrease in scoter numbers. Up from nearly 500 the day before to less than 70 the day following. 

The Bluff:

There weren't any other parties that I am aware of that were lakewatching simultaneously that day. I can't blame them—the weather didn't look nearly as ideal as the days preceding, and it was of course the holiday Monday. As such, no direct comparisons can really be made. However, given how slow it was at The Bluff, we left early to check out Grand Bend Beach, which we found to be similarly slow. The highlight here were three Black Scoters.

Grand Bend Beach:

I also did a quick lakewatch at Waterworks Road, but it was getting on in the morning and basically nothing was happening. 

Waterworks Road:


Anyways, it was an interesting weekend, and with the good coverage, a lot of interesting comparisons could be made. It is noteworthy how slightly different orientations, and proximity to the "funnel" at the south end of the lake affect the species composition and diversity. It is fun to speculate—I'll let you reach your own conclusions. 

Wednesday 26 April 2023

Birds from "Across the Pond"

This past month has been particularly exciting for birds that normally are not found in North America (or at least, are exceptionally rare) here in Ontario. While I am not really one to chase birds for my (modest) Ontario list anymore, I certainly could not pass up the opportunities that were presented to me to see some special birds. I will detail these such instances.

The first was on April Fool's Day (April Fowl's Day). On March 30th, Dave Worthington found a Pink-footed Goose in Corner Marsh in Whitby (Durham Region). This represented the furthest west this species has ever been recorded in the province, with all previous records occurring in far Eastern Ontario. This species was first recorded in Ontario in November 2015, and has been nearly annual since. A pattern of vagrancy has recently been well established in Northeastern North America. 

I have a soft spot for waterfowl, and it just so happened that Pink-footed Goose was top of my list of "most wanted" species for the province (and really, just in general). This may have something to do with it proving to be a major plot point in the 2012 film, "The Big Year" :) 

I was still in Guelph at the time, and contemplated going when it was first found. I decided not to, although likely would have if it was somewhere I didn't have to drive through Toronto for. Although I certainly wanted to see it, it wasn't eating me alive or anything to not be.

As luck would have it, the bird was refound the next day in York Region at Reesor Pond in Markham, and was seen going to roost with the Canada Geese that evening. As such, I found myself in the wee hours of the next morning driving towards Markham, picking up Nate Klassen and Dennis Dirigal en route. It was an hour and a half drive from Guelph, which seemed much better than the several hour drive it would have been had I been going to Ottawa to try and see this bird, where they normally show up. 

When we arrived, we were greeted with dozens of birders and a thick wall of fog. The fog didn't lift for the better part of a half hour, but when it did, we were greeted by the target goose. It stuck around for a bit in fantastic lighting before taking off for the day to feed in nearby fields. A big highlight for me was hearing it vocalize a few times!

It was a pretty fun morning twitch! As a side note of interest, I have also seen a Barnacle Goose, another rare European vagrant, in York Region. I imagine that York has the best goose list of any Ontario County, with the exception of some Eastern Ontario counties.

The other fun twitch happened just a few days ago, on April 23. I was out for a morning walk around the neighbourhood (highlighted by my patch bird Gadwall, long overdue and quite exciting), when I saw a report come in for a White Wagtail, the second provincial record, in Simcoe County, in Angus (near Barrie). This would have been about a three hour drive from London, and although I was briefly tempted, I was quite content to let this bird slide.  

I got a call not too long after from Bill Lindley asking if I wanted to drive up with him. Well, that settled it. I figured I could justify a road trip with a friend. Bill picked me up about half an hour later, and we were on our way.

We decided to travel the back roads on the way to Angus. I knew the route quite well, having taken it when I drive up to Algonquin. It is a pretty nice drive, and certainly more scenic than the 401 (not to mention more relaxed). Highlight from the drive was a Snow Goose in a field right beside the road.

Bill and I arrived along McKinnon Road in Simcoe County right around 2pm, and immediately was directed to the bird by the many birders already on scene. It was far back in the muddy field, and my photos are best described as "poor", but you can tell what it is. 

There are several subspecies of White Wagtail, and they occur throughout much of Europe and Asia. This particular bird is of the subspecies ocularis, which is the Siberian subspecies. This subspecies also breeds in low numbers in Alaska. The only other Ontario record was from April 2017, and was of the subspecies yarellii, which is much rarer in North America, and comes from a completely different part of the species' range. Quite interesting, I think. 

Anyways, that's my story about seeing two birds from "across the pond"!

Saturday 18 March 2023

Orchids of Algonquin Provincial Park

Orchids (Orchidaceae) are a particularly enchanting group of plants that delight many botanists. There are over 60 species that inhabit Ontario, 36 of which can be found in Algonquin Provincial Park, located in Central Ontario. Algonquin Park is home to a variety of different habitats, which helps explain its orchid diversity. 

While I am not nearly as orchid obsessed as some, I do enjoy seeing these beautiful and unique wildflowers, so I have made it a point of seeking out the species that occur in Algonquin Park. I have only managed to see a little over half of them within the park boundaries, and have seen several more of the species elsewhere. In this post, I will attempt to highlight and provide a brief overview the species that can be found in the Park, in alphabetic order as they appear in the Checklist of Vascular Plants of Algonquin Provincial Park (2020) by Sean Blaney et al. I will make reference to the West and East Sides of Algonquin Park in this post. The West Side is higher in elevation, comprised mostly of upland sugar maple-beech forests on glacial till. The East Side is lower in elevation, comprised largely of pine forests on sandy glacial deposits. Of course, there is some overlap in the habitat types.   

Dragon's-mouth (Arethusa bulbosa) is a particularly charming little species of orchid that hits peak bloom in late May into early June. This is a rather rare species in Algonquin Park, with most of the records coming from the Park's East Side. Despite it's apparent rarity, it is likely widespread, albeit in low densities, and just under detected. It is often found growing on bog mats. 

Dragon's-mouth (Arethusa bulbosa)

Sort of looks like a dragon!

I'm not entirely sure what the mechanisms are behind the species' distribution in the Park. The above individuals were photographed in a location with some unique associates, Meagre Sedge (Carex exilis) and Buckbean (Menyanthes trifoliata). 

Tuberous Grass Pink (Calopogon tuberosus) is a fairly familiar orchid to those who many find themselves in a bog during early summer. This orchid is special in that its flowers are upside down. It is not particularly common in Algonquin Park, but is widespread. 

Tuberous Grass Pink (Calopogon tuberosus)

Frog Orchid (Coeloglossum viride) is not common anywhere in Ontario, and is considered rare in Algonquin Park. The only record(s) are from the West Side. I have not seen this species in the Park.

The coralroots are always fun. By far the most abundant is Spotted Coralroot (Corallorhiza maculata), and both the western (var. occidentalis) and eastern (var. maculata) varieties can be found. Early Coralroot (Corallorhiza trifida) and Striped Coralroot (Corallorhiza striata) are also known, but are not as commonly encountered. The latter is rare and only known from the East Side. Coralroots are well known to be mycoheterotrophic orchids

Spotted Coralroot (C. maculata var. maculata)

Spotted Coralroot (C. maculata var. maculata)

Probably the most well known of Algonquin's orchids are the lady's-slippers. Only one, Pink Lady's-slipper (Cypripedium acaule) is common. You are more than likely than not to encounter this species somewhere in your travels during June and early July in the Park. 

Pink Lady's Slipper (C. acuale) (London, ON)

Ram's-head Lady's-slipper (Cypripedium arietinum) also had records from Algonquin Park, on the East Side. The last record was in 1982. Last June I embarked on a backcountry journey to check out where they were last seen, but came up empty. I thought for sure that they must be extirpated...that was until late August. No, I did not find Ram's-head, but I did have a conversation with Dan Brunton over a lunch break during a day of botanizing. He indicated that the area I had checked for the species was, although suitable, not where the records had come from. So maybe we shouldn't say the population is gone just yet. That being said, this species is particularly sensitive to disturbance, and is apt to disappear, so the optimism may be in vain. Perhaps this will be a goal of 2023. 

The only non-native species of orchid in Algonquin Park, and one of very few in Ontario, is Broad-leaved Helleborine (Epipactis helleborine). In Algonquin, it is most often seen in areas of human disturbance, although it was growing was commonly along the Bonnechere River floodplain last Summer (not directly beside development, although quite close). It is increasing in abundance, although I don't think necessarily poses a risk to native flora.

Broad-leaved Helleborine (E. helleborine)

The rattlesnake-plantains are another group of interest. All four of Ontario's species are known from the Park. Checkered Rattlesnake-plantain (Goodyera tesselata) is likely the most abundant, followed by Dwarf Rattlesnake-plantain (Goodyera repens). Downy Rattlesnake-plantain (Goodyera pubescens) is rare and only known from the West Side. Western Rattlesnake-plantain (Goodyera oblongifolia) is only known from three or so West Side records. 

Checkered Rattlesnake Plantain (G. tesselata)

Lesser Rattlesnake Plantain (G.repens)

Downy Rattlesnake Plantain (G. pubescens)

Western Rattlesnake-plantain (G. oblongifolia) (Bruce Peninsula, ON)

Fen Orchid (Liparis loeselii) is another rarity in Algonquin Park, although there are records throughout. I have not seen this species in the Park. I have to wonder if its habitat requirements are particular, and perhaps the required nutrients just are not common in Algonquin Park. 

Fen Orchid (L. loeselii) (Puslinch, ON)

There are two species of adder's-mouth that are found in Algonquin Park. The first is Green Adder's-mouth (Malaxis unifolia), which, while not common, is found throughout. This is a tiny, delicate orchid that is always a delight to see. The second is White Adder's-mouth (Malaxis brachypoda). This species appears to be a calciphile (likes calcium-rich substrates), so it is not found widely in Algonquin Park. In fact, the only area it is known, to my knowledge, is in the Brent Crater on the East Side. The Brent Crater is unique in that it hosts the only visible limestone (a calcium-rich rock) in the park, so there are a few floristic elements that reflect this. I haven't seen this species in the Park, but have photographed it in the Ottawa Valley, growing in a cedar swamp, similar habitat to which it would occur in Algonquin . 

Green Adder's-mouth (M. unifolia)

White Adder's-mouth (M. brachypoda) (Arnprior, ON)

The twayblades are a favourite group of mine. None of them are common. Heart-leaved Twayblade (Neottia cordata) is the only species found on both the West and East Sides. It grows in shaded bogs. Broad-lip Twayblade (Neottia convallarioides) is found in a few spots on the West Side, and Auricled Twayblade (Neottia auriculata) is found in a few spots on the East Side, both in riparian habitats. Southern Twayblade (Neottia bifolia) is the real crown jewel, and is likely the rarest species of plant in the Park, ranked S1 in Ontario. It is found on the East Side. There's so much more I could say and speculate about the ecology of Southern Twayblade, however I'll omit it here in fear of saying too much :)

Auricled Twayblade (N. auriculata)

Southern Twayblade (N. bifolia)

Southern Twayblade (N. bifolia) — "bifolia"

Now into the bog orchids, buckle up. 

Tall Northern Green Orchid (Platanthera aquilonis) is rare throughout the Park. White-fringed Orchid (Platanthera blephariglottis) is another mega rarity in the Park. It is only known to be extant in one location, and is considered historical from the West Side. Truly a special species. The most common of the bog orchids is Club-spur Orchid (Platanthera clavellata) is is found in most suitable habitats. Tall White Bog Orchid (Platanthera dilata) is quite rare in the Park, only known from one location on the East Side. Northern Tubercled Orchid (Platanthera flava var. herbiola) is rare, but can be found locally abundant along the Petawawa River system on the East Side of the Park. Hooker's Orchid (Platanthera hookeri) has earned the designation of "common" in the checklist, however I doubt this is actually the case. All the records are from the East Side of the Park. Ragged Fringed Orchid (Platanthera lacera) is rare, but can be found in the right habitat, often fens or bogs. Blunt-leaved Orchid (Platanthera obtusata) is quite uncommon and widespread. Lesser Round-leaved Orchid (Platanthera orbiculata) is the species of bog orchid you are most likely to encounter in the forests, where it is uncommon. Finally, Small Purple Fringed Orchid (Platanthera psycodes) is only known from the East Side, where it is not particularly uncommon. 

White-fringed Orchid (P. blephariglottis)

White-fringed Orchid (P. blephariglottis)

Club-spur Orchid (P. blephariglottis)

Tall White Bog Orchid (P. dilatata) (Ottawa Valley, ON)

Northern Tubercled Orchid (P. flava var. herbiola)

Hooker's Orchid (P. hookeri) (Arnprior, ON)

Ragged Fringed Orchid (P. lacera)

Blunt-leaved Orchid (P. obtusata) (Longridge Point, ON)

Lesser Round-leaved Orchid (P. orbiculata)

Small Purple-fringed Orchid (P. psycodes)

Likely the most abundant bog dwelling orchid is the Rose Pogonia (Pogonia ophioglossoides). This species adorns bog mats in shades of pink during the early summer, and is often quite numerous. 

Rose Pogonia (P. ophioglossoides)

Lastly, we have the ladies'-tresses, which made late summer exciting for the botanist. Four species can be found in Algonquin Park. The most abundant is Sphinx's Ladies'-tresses (Spiranthes incurva), part of the Nodding Ladie's-tresses (Spiranthes cernua) complex—it was formally known under this name. This species can be found quite readily in the latter half of August, often growing abundantly in wet areas, including the ditches of Highway 60. The most impressive showing I have seen of this species is along the shore of Lake Travers. Northern Slender Ladies-tresses (Spiranthes lacera) are locally common. This species seems to like dry, open areas. I have seen this species in good numbers the the Old Airfield. Hooded Ladies'-tresses (Spiranthes romanzoffiana) is only known from the West Side, but must certainly occur on the East Side too. This species likes wet areas, so is most likely to be seen in fens. Finally, Cases' Ladies-tresses (Spiranthes casei), which bit of an enigma for me. It is considered quite uncommon in Algonquin Park. I have spent a fair amount of time looking for the species in suitable habitat (dry, open areas), but have so far come up empty. Supposedly, it flowers the latest of these four species. 

Sphinx's Ladies'-tresses (S. incurva)

Hooded Ladies'-tresses (S. romanzoffiana)

Hooded Ladies'-tresses (S. romanzoffiana) — note "fiddle-shaped" lip

Northern Slender Ladies'-tresses (S. lacera)

Northern Slender Ladies'-tresses (S. lacera)

Of course, part of the fun of botany is finding new things. There are a few species that could still be found in Algonquin Park, and I will highlight some here.

Two species that very well may already have been observed in the Park, but have not been confirmed via adequate photos and/or specimen are Green Bog Orchid (Planathera huronensis) and Large-leaved Bog Orchid (Platanthera macrophylla). In just the last couple of years, for example, I know that a likely individual of the former has been seen in Basin Depot, and the latter, a good candidate individual comes from near Galeairy Lake. Green Bog Orchid in particular is a glaring hole in the list, as it is likely one of the more abundant bog orchids in the province.

Green Bog Orchid (P. huronensis) (Cochrane, ON)

Now for some other potential additions—there aren't many! Starting with the most far-fetched...Yellow Lady's-slipper (Cypripedium parviflorum). This species prefers calcium-rich environments, which are lacking in Algonquin Park. Despite the low possibility of its occurrence, I include it simply because of how distinct and conspicuous it is—if its there, it will be seen. Like the White Adder's-mouth, if it is anywhere, it would probably be in the Brent Crater. That being said, I don't think that the Bonnechere River Valley in Basin Depot should be excluded from the list of possibilities. This is a good segue into the next species, Showy Lady's-slipper (Cypripedium reginae). I suspect this is another species with calciphilic tendencies. There is an iNaturalist record from Round Lake, which is tantalizingly close to Algonquin, and in particular, where I suspect it could occur—Basin Depot. In conversation with Dan Brunton, Basin Depot seems to have some sort of calcaerous element to it (the two of us found Bromus kalmii there last August, only the second record for the park, and a species associated with more nutrient rich environments), and it is largely unexplored by botanists, so who knows! As the name would suggest, the species is quite noticeable, so it won't be a matter of overlooking it. Lastly, I have my top pick for most likely addition, Shining Ladies'-tresses (Spiranthes lucida). This species stays true to the common theme here of prefering calcareous habitats, which does slightly hurt the chances of it being in the Park. That being said, it is fairly small, and easy to overlook. I observed this species fairly abundantly along the Ottawa River last June (it is the earliest flowering Spiranthes), and it sort of planted the seed in my mind that it could occur along one of the East Side rivers in Algonquin Park. The two places that immediately come to mind are the Barron and Petawawa Rivers, tributaries of the Ottawa River. These rivers also reside along geologic fault lines, which may mean there is a bit of calcium here and there (while not super common, there are a few calciphilic plants along these rivers). A fun thought, anyways! 

Yellow Lady's-slipper (C. parviflorum) (London, ON)

Showy Lady's-slipper (C. reginae) (Ottawa Valley, ON)

Shining Lady's-tresses (S. lucida) (Arnprior, ON)

And just so I can say "I told you so" when one of these randomly pops up out of the blue in true Algonquin Park fashion, keep an eye out for Fairy-slipper (Calypso bulbosa) and Small Round-leaved Orchis (Galeris rotundifolia). Both have historic records from the Ottawa Valley, so why can dream.

So there you have it, the Orchids of Algonquin Provincial Park. What a wonderful place to observe these wonderful plants that provide endless joy in discovering, as well as crucial information on the habitats in which they occur.