Thursday 26 September 2013

Great Egret roost in Waterloo Region and the power of eBird

For the past two months Great Egrets have been roosting nightly at the Hespeler Mill Pond. On August 24, Ken, my Dad and I had the chance to meet up with (sort of) retired CWS researcher Chip Weseloh to try to make an accurate count of the number of individuals utilizing this roost. We weren't disappointed as we had at least 19 birds sitting out in the middle of the pond before sunrise.  Shortly after we arrived they started dispersing as is normal for these birds.
Part of the roosting flock

While this behaviour is quite common at this time of year for Great Egrets, it provides a really nice example of the utility of eBird to gather data to monitor such a roost.  This roost is especially well-suited to being monitored by Citizen Scientists because it is easy to observe and it is relatively close to a large population of birders.  In fact, since June of this year there have been at least 99 surveys done at Hespeler Mill Pond resulting in over 110 checklists being submitted to eBird!
A screen-shot showing recent Great Egret sightings at Hespeler Mill Pond
This is the really amazing thing about eBird - something as simple as going birding in your local neighbourhood can shed light on bigger questions.  In this example we can answer several:
1. When do Great Egrets start building in numbers at fall roosts?
2. When do Great Egret numbers peak at fall roosts?
3. How many individuals are using a particular roost?
4. Do numbers stay steady at a roost?

Obviously, there are many more questions that can be answered - these are just a taste. And when you think about the fact that millions of bird observations are submitted every month to eBird, the questions you can start answering are practically endless! And these are exactly the sorts of questions that scientists working for governments with increasingly fewer resources could never fully answer.

I'll leave you with this final figure showing all of the counts of Great Egrets from Hespeler Mill Pond by date for this year:

Great Egret counts from Hespeler Mill Pond on eBird

Chip Weseloh and Tyler Hoar recently published a paper where they used eBird to track the northbound migration of Great Egrets towards Ontario using eBird, I'll try to find a copy of that and post the link.

And if you aren't yet submitting your everyday bird records to eBird, hopefully this will convince you that it is more than worthwhile - every observation is a small piece of a huge puzzle!

Monday 16 September 2013

Comet Darner from Brantford

Earlier this year, Bill Lamond found a few Comet Darners at a pond in Brantford. So one weekend back in July when I was back home Ken, Erica and I decided to check it and weren't disappointed.  The pond didn't look like much (it is a drainage pond less than 1/2 hectare in size in an industrial park), but it was absolutely teeming with dragonflies.  When we arrived there were hundreds of Black Saddlebags, Widow Skimmers, Twelve-spotted Skimmers and Familiar Bluets (amongst a few other species) but it didn't take us long to find our target:

Comet Darners are historically very rare in Ontario, typically being found only to our south. In fact, when the current Ontario Odonata Atlas species maps were done up in the early 2000s the map for Comet Darner had only 2 records on it! However, in the last several years we have seen an increasing number of records, still all from southern Ontario where migrants are more expected.  It is hard to know for sure whether the increase in records is real or just an artifact of the greatly increased search effort by the growing number of dragonfly enthusiasts in Ontario.  Realistically, it is probably a combination of those two factors.

The Brantford record is especially intriguing because Bill also found Comet Darner at this location last year, which may suggest that the species successfully overwintered at the site - something that hasn't been demonstrated yet for Ontario.  We did a quick search of the shoreline for exuviae but were unsuccessful in finding any.  Of course, with the abundance of other migrant species at the site, maybe it is just the perfect spot for migrant species to drop in to...

This species is similar to the familiar Common Green Darner, but the red abdomen is really distinct.  Another easy field mark is the patterning of the postfrons (think of it as the top of the 'nose') - on Common Green Darner there is a "bulls-eye" pattern, while Comet Darner is plain:
Top view of head and postfrons of Comet Darner
Top view of head and postfrons of Common Green Darner
If you are at all interested in Odonata in Ontario, be sure to check out the Ont-Odes google group and submit your sightings to the Ontario atlas (details here).  There is also a course being offered at Long Point Bird Observatory at the end of the month that you might be interested in!

Saturday 14 September 2013

Gannet in The County!

I decided yesterday that I was overdue for a trip into "the county" as people around here like to call it. My first stop was Charwell Point, an amazing spot that Brandon showed me not long ago - it has a nice mix of habitats: a good duck/heron pond, a beach, and an area of big willows that attracts migrant passerines. It is also a small peninsula in Lake Ontario.

I was happy that I brought rubber boots; even with them I almost got wet crossing the "gull pond" that is in the middle of the point.  I suspect that because the water is so deep there this year, duck hunters weren't using the spot as frequently.  It was quiet for birds, so I decided to do a short lake watch at the end of the point.  I'm glad I did! After not seeing much I noticed a big white bird coming in from the east -  I put up my binoculars and was floored to see an adult Northern Gannet! I snapped a couple photos as it flew by. I pulled my scope off my tripod and set my camera on it to get a video of the bird once it had landed on water.  The bird continued further and further back to the east, where I eventually lost it.  The entire duration of this was 5 minutes (9:25 - 9:30 am).

Here are some pics and a video (you need to watch the video in HD otherwise you don't see much):

That was the highlight of the day, however, bird activity did pick up: I saw a couple nice flocks of warblers and I finished at Charwell Point with a decent 63 species.  See my complete eBird checklist.

Gannets, while common at breeding colonies (like Bonaventure Island) and elsewhere on the east coast are very rare here in Ontario, with usually only a few per year at best. Of those, the vast majority are first year birds that presumably wander up the St. Lawrence and eventually make it to Lake Ontario. In fact, prior to 2013 there were only 3 records of adult gannets accepted by the OBRC:

-May 13, 1983 at Prince Edward Point, Prince Edward County found by RKF Edwards
-November 24, 1990 at Moore Point, Durham Region found by Brian Henshaw
-October 23, 2012 at Netitishi Point, Cochrane District found by Josh Vandermeulen and Alan Wormington

The bird I saw is quite likely the same adult gannet that has been "stuck" on Lake Ontario for several months.  Here's the eBird map showing gannet sightings in the past year:

Adult gannet sightings from Lake Ontario in eBird since last fall
Those records, plus a couple not shown on this map that I knew of (please contact me if you know of others) are listed below in chronological order:

-September 1 at Hamlin Beach State Park, Monroe County, NY by Dave Tetlow
-October 13 at Gravelly Bay, Jefferson County, NY by Antony Shrimpton
-October 21 at Derby Hill, Oswego County, NY by Bill Purcell and Ken Burdick
-May 1 at Prequ'ile Provincial Park, Northumberland County, ON by Fred Helleiner
-May 7 and 18 at Hamlin Beach State Park, Monroe County, NY by Andrew Guthrie
-July 25 at Presqu'ile Provincial Park, Northumberland County, ON by Steve Oswald
-September 1 at Brandon's Condo, Hamilton, ON by Brandon Holden
-September 10 at Colonel Sam Smith Park, Toronto, ON by Garth Riley and David Pryor

Given the rarity of adults on Lake Ontario, there is a strong argument to be made that these all involve the same bird.

Thursday 12 September 2013

eBird's hotspot explorer launched!

The eagerly (by some) anticipated public launch of eBird's latest data visualization tool happened today.  If you are at all interested in bird distribution or citizen science then you'll want to check it out!  Below you'll find a quick run-through of how I use the Hotspot Explorer. You should also read the excellent summary by Dick Cannings here.

To get to the Hotspot Explorer just go to eBird and then click the "explore data" tab and then click on the hotspot explorer link.

Once you get to the Hotspot Explorer you'll get a page that looks like this:

That's a grid showing species richness by colour (yellow = low, red = high). Remember, this is only as good as the data that goes into eBird, so it is far from complete, especially outside of North America. You can zoom in on particular areas, like North America or Ontario:

You can click on any one of the grid cells to bring up a species total - that's the total number of species reported to eBird for that grid cell. Zooming in further brings you to the hotspot view:

This view is also really cool because it shows you individual hotspots colour-coded for species richness.  So you can quickly find which spots you should check out!  You can also refine the date-range, so if you are interested in finding out which are the best spots in September you can do that, or maybe just for the past two months!

Clicking on an individual hotspot marker will bring up some quick info about that hotspot:

In the example above, the hotspot name is Hillman Marsh Conservation Area, it is found in Essex County (Ontario) and there are 291 species reported to eBird and 1057 checklists (not too bad!). There is also a link here to the Bar Chart, High Counts, and directions (a google map of the hotspot).  Pretty handy.

But the real fun starts by clicking the View Details button:

This gives you a complete list of species for that hotspot and details of the most recent record for each species.  You can sort this list taxonomically by clicking "species name" at the top of the list or you can sort by last record date by clicking the "last seen" at the top of the list.  You can bring up the complete eBird checklist by clicking the date of any record.  At any time we could change the output by date, too.  So if we wanted to see the details for this year only, or for the month of May only, it is only a matter of changing the date settings at the top of the screen.

In addition to the species list, there is more details on the right hand side of the screen:

This shows first the "Top eBirders", the top 10 eBird users based on species or checklists submitted (just click the button to toggle between the two).  This is where the real genius of eBird's deveolopers comes in...they know some birders just won't be able to resist this challenge of moving up "the rankings".  Have a look at your local hotspots - are you in the top 10? If not, this is the official firing of the starting gun!

Below the Top eBirders section is a list of recent visits - this is also very handy.  You can see who has been birding recently at this hotspot and how many species they saw - click the date and you'll be taken to the complete list of what they reported!

Anyways, I can attest that this is a really fun new tool, and highly addictive! Definitely give it a try (you don't have to be an eBird user) and see if you can move up the rankings on your local hotspot!
If you notice that a hotspot is missing, that means you should suggest it! Here's how to suggest a location as a hotspot:
1. If the location is already in your account, you just have to sign in to eBird, click "My eBird" then "Manage my locations" - find the location name in your list of locations and check the checkbox beside the location name.  Then, at the top of the screen there is a little dropdown menu - click that and select "suggest as hotspots", finally, click the "submit" button beside the dropdown and you are done.
2. If the location is not already in your account, you just have to sign in to eBird and go to submit a checklist. When choosing your location for the checklist use the "find it on a map" option and plot the new location on the map.  Give it a name and then check the "Suggest as a birding hotspot" checkbox before clicking the "Continue" button.  That's it - you can just stop entering your checklist now because the location has been created and submitted as a hotspot suggestion.

In both of those scenarios the hotspot has been submitted to the hotspot reviewer team.  It could take a couple days for them to approve it or they may contact you for more information.  This is how we avoid having things like people's yards made into hotspots (unless they really are!).