Showing posts with label ebird. Show all posts
Showing posts with label ebird. Show all posts

Sunday, 3 March 2019

Barred Owl Barometrics

Owls are a favourite bird of many people, even non-birders. So when a Barred Owl showed up at Rondeau Provincial Park this past December, and has been seen intermittently as recently as yesterday, it is special. This bird is only the fifth known record for the Rondeau checklist area.
There is lots of suitable habitat for Barred Owl at Rondeau, and that begs the question as to why it is so rare. Of course looking at the very limited habitat across much of southwestern Ontario, there aren't many habitat linkages so birds from the species' normal range choosing the best habitat available to them would not be tempted to move into the Rondeau area.

But that may be changing, and not just because the amount of forested habitat here in the southwest is increasing to any extent. For some reason, Barred Owls have been recorded a lot more this winter than usual. It was interesting to read the various Christmas Bird Count reports for this past Dec 15-Jan 5 period to see where these owls were recorded more frequently than usual. Many counts only record them very infrequently if at all, so getting even one was a highlight. Some CBCs had them in record numbers. Okay, usually a single bird was a normal number reported in previous counts, but some counts were reporting as many as 3 birds. The summary reports provided by the count compilers on Ontbirds often made special mention of the presence of Barred Owl on their count.
I did a bit of search on eBird. This first map shows the Barred Owl reports on eBird during the three month period of December 2005 to February 2006 period. The purple rectangles indicate where one or more reports of Barred Owl occurred during that time. The darker the purple, the more reports within that rectangle.
Obviously there were very few reports during that period. However since eBird only got up and running in 2002, lots of birders had not begun participating, so it is not surprising how few records show up. In fact the grey rectangles indicate where there was at least one report of any bird species made, and the non-grey and non-purple rectangles indicate where there were no reports of any birds. There are probably as many rectangles without any birds as with at least one bird, and clearly Barred Owls were very limited.

This next map shows a similar area for the period of Dec 2010 to Feb 2011. Obviously the number of birders participating in eBird seems to have increased, given the increased number of grey and purple rectangles. And the number of purple rectangles has also increased. But the level of participation by birders entering data on eBird was still building, and it is not nearly at the same level as it is today.
This next map shows the period of Dec 2017 to Feb 2018, just a little over a year ago. The number of grey rectangles has increased quite a bit, as have the number of purple rectangles. It is interesting to note that across the border to the southeast of southwestern Ontario, it seems that the increase in purple rectangles is even greater.
Fast forward to the most recent three month period of Dec 2018 to Feb 2019. While the number of rectangles where bird data has been entered is much the same as the previous year, there is definitely an increase in the number of purple rectangles, including more darker purple ones.
As expected, the level of bird data entry on eBird continues to grow. It will be interesting to see what next year's map will look like. Will the species continue to appear to expand? Will there be a retraction?

The area shown on these maps is not the only area where Barred Owls have apparently increased. A recent news report from Nova Scotia, shown here, indicates the species has increased there as well. It has perhaps been a trend throughout the northeast, and the question is why. Has the weather been a factor, or the food available during the breeding season, causing a greater production of young, but during the winter the food availability is not enough to sustain the increased population so birds have to move beyond their normal range? This has certainly been the case for some other owl species, such as Snowy Owl. It is interesting to speculate, but for the time being we can enjoy the presence of this impressive owl.
Another thought to consider: maybe there is more than one Barred Owl in the Rondeau area. There certainly is enough habitat. As the mating season arrives, we will have to get out in the evening and listen for calling birds. Just maybe there is a pair of them and seeing more of this species is in our immediate future!



Thursday, 21 April 2016

Before there was ebird......

Once upon a time, there were no computers, no cell phones, no Ontbirds, no ebird........none of a lot of things that we take for granted now. Hard to believe, isn't it, especially for the generation that has grown up with all of these technological advancements literally at their fingertips. But birders back then were still plentiful, and got out to enjoy the natural world unencumbered by the myriad digital devices we can't seem to live with out nowadays. Instead, we heard about good birds by the proverbial grape vine.....a.k.a. a telephone land line. Or by reading the weekly column of writers such as Peter Whelan (Globe and Mail) or Tom Hayman (London Free Press). Just imagine......

Sure the optics weren't great by today's standards. In fact just earlier this week I was reminiscing with a former colleague with whom I worked at Rondeau 42 years ago, that the old Bushnell Spacemaster telescopes and the Bushnell Sport Custom binoculars, both of which were the industry standards for birders of that era, aren't much better than museum pieces or door stops now (packrat that I am, I still have my original Spacemaster, and both of my original Sport Customs (7 X 35 and 9 X 36) from the 1970s, but not my even earlier two pairs of binoculars...a Kmart special 7 X 35 and a model of Tasco 7 X 50 :-).
Prothonotary Warbler, first discovered nesting in Ontario and Canada in the early 1930s
Why this bit of 'recent' history? Well, if you have been keeping up with the latest information on ebird as it pertains to the milestone reached by Ontario birders, you will be aware that just a few weeks ago, the one millionth ebird list for Ontario was entered onto the site.

It was submitted by yours truly.

I didn't realize it at the time, of course, but was contacted a short time afterwards to inform me of that event. (I didn't get any prize, just the notoriety :-) And interestingly it was an historic checklist that I submitted. You can read about that occurrence, and the way ebird has taken off in Ontario by clicking on this link.

Just like birding, I was at the right place at the right time to have submitted the list that reached this significant milestone for Ontario birders. In reality, I have only been submitting to ebird for about a year and a half, with a total of 522 lists submitted in that time. Some of them are historical ones.
American Avocet, June 2013
 Like many birders who collect data in one way or another, I have stacks of old checklists and field notes going back to the early 1970s. I began birding about a decade before that, but never bothered to keep lists until the early 1970s. One wonders if all of those notes and lists would ever be useful, so rather than just put the checklists into the recycling bin, I decided to put that data to some use (hopefully!). That is how I happened to submit the one from September 26, 1984, which was the one millionth list.
Black Vulture, March 2009

(Note to self: get busy with all of those other historical lists!)

Just like optical equipment, bird checklists have evolved. In digging through Rondeau's historical files, the park staff very recently came up with the two featured in the next photo. The one on the left is dated 1956, and had accumulated 268 species by that time, and the one on the right is dated 1959, with 275 species. The park naturalist of that era, R. D. Ussher (RDU), was a forester by training, but a pioneer in natural history interpretation of Ontario's provincial parks, and he was at Rondeau from 1952-1969. He compiled and maintained checklists of birds, mammals, plants (both woody and herbaceous) as well as reptiles and amphibians. There were records from Rondeau even back into the 1800s, all of which he or others scoured through to come up with these lists, and were the basis for checklists that followed.
There was a handful of seasonal naturalist leaders at Rondeau from the time that Dick Ussher retired, until the time that I came on in a full-time capacity which, including some summer positions while I was at university, went from 1973-1986. I valued the checklists that RDU had compiled, and did my best to build on them. My first effort was this booklet, shown below, produced in 1976. I borrowed the B&W illustration of the Black-crowned Night-Heron from the 1974 checklist that was produced by Howard Coneybeare, a talented and prolific illustrator of many Algonquin Provincial Park publications, who was supervising Rondeau's natural history interpretation program in 1974. I looked for a copy of that list but it must be buried too deep.

By 1976 there were 301 species on the list.
1976 checklist
Instead of just a list to check off birds that had been seen, I decided to put some seasonal information along with it, as is shown in these open pages of that checklist.
That was popular, and we quickly ran out. That design was also more expensive, so we went back to the folded card stock in 1977, which by now had 303 species.

By 1980, it was time to update the checklist once again, as it now had 317 species.
1980 checklist
By 1984, we had accumulated 332 species.
1984 checklist
By 1992, the list had grown to 334 species, and had a slightly different look to it.
This one was reprinted a few times, until the Friends Of Rondeau began producing it and selling from their bookstore. It now looks like this, although it has had a few reprints/updates with more or less the same cover:
The cumulative total for the Rondeau checklist area at the point of the most recent printing, in February 2015, stood at 362 species. With the addition of the Say's Phoebe of September, 2015, the next update will be at least 363 species.
Say's Phoebe, Sept 17 & 18, 2015

Magnificent Frigatebird, 2012