Tuesday, July 31, 2012

Cowbird Parasitism of a Blue-grey Gnatcatcher Nest

I started this posting on the 12th of July and never got around to posting it until now. I really wanted to write a long discussion on the topic that got into urban sprawl, habitat fragmentation, and how our economic system demands that we grow our population.... But I'll just leave it as a posting about what the title says.

Three years ago when I started birding, I had photographed this bird (above) at the Ojibway feeder station. I didn't really know what the bird was but eventually identified it as a Brown Headed Blackbird.  I came to find out that this is not a bird that birders like, due to its reproductive strategy. According to the Smithsonian National Zoological Park (SNZP): "A single female (cowbird) is capable of laying nearly one egg per day at the peak of the breeding season, and produces a total of 30-40 eggs over the 2-3 month breeding period (May-July). Because female cowbirds usually lay only one egg in a host nest, this translates into 30-40 nests parasitized (usually of at least several different species) per female in one season." (Petit)

SNZP continues to describe the parasitism strategy as follows: "Typically, female cowbirds find potential host nests by perching during early morning hours in a location with high visibility such as a dead tree in a forest opening, observing behavior of host females that are building nests, and following the unsuspecting birds directly to their nests. Once the nest location is known, the cowbird returns during the egg-laying period of the host female and deposits her own egg in the nest"(Petit).
Blue grey Gnatcatcher, in front of its nest

So, a few days ago, I had noticed a very gregarious pair of Blue Grey Gnatcatchers as I was walking at Ojibway Park. I noticed them feeding their fledglings at their nest (see above). A few days later, I went back to observe the nest (from a safe distance of course) and was saddened to see a large brown bird perched on the tiny moss and lichen Blue-grey Gnatcatcher nest.  Imagine how angry, confused and sad the parents are when they realize the fledgling they spent all of their energy on isn't even their own.
Large Cowbird Fledgling on a Blue-grey Gnatcatcher nest
Habitat fragmentation & Urban Sprawl

Pg 114 of Sibley's Guide to Bird Life and Bird Behavior has an excellent diagram that I wanted to put here but I want to respect the copyright restrictions of the books and may elaborate on the topic in a later blog posting.

How our economy grows & Urban Sprawl

Again, I lack the time  to elaborate on this topic at present, but hopefully I can push it into an upcoming posting. I wanted to consider the idea that economic growth can come from two major sources: 1-Export Innovative products (such as Ipods and Windmills) and 2-grow the population. I also wanted to get into Dutch Disease, an economic term, not biological. Natural resource extraction in Canada, particularly the Alberta Tar Sands tend to increase the value of our currency, which hurts other sectors such as manufacturing. We've seen the Canadian dollar at parity with the US dollar for the last few years as well as an exodus of manufacturers from Ontario. I guess these ideas could be considered totally off topic, but I really wanted to tie in how this Brown headed Cowbird fledgling sitting on a Blue-grey Gnatcatcher nest is symbolic of our how we are affecting our ecosystems. Economics tells us that we will continue to fuel our system with more growth, more urban sprawl, more fragmentation and resource extraction, all things that will continue to hurt our ecosystems and give the Brown headed Cowbird the perfect conditions for it to thrive.

Good Birding,

Further Reading:

Petit Lisa, "Brown-headed Cowbirds: From Buffalo Birds to Modern Scourge", Smithsonian National Zoological Park, ND, WEB, July 12, 2012 , http://nationalzoo.si.edu/scbi/migratorybirds/fact_sheets/default.cfm?fxsht=3

Boesveld Sarah , "Efforts to curb urban sprawl not working - Jobs are following in the outward expansion of cities", Vancouver Sun, June 18, 2012, WEB, July 12, 2012, http://www.vancouversun.com/news/whoarewe/Efforts+curb+urban+sprawl+working+census+shows/6174917/story.html

Wikipedia, Habitat Fragmentation, http://en.wikipedia.org/wiki/Habitat_fragmentation

Cowbird and Upland Sandpiper in Glencoe Ontario.

Wednesday, July 25, 2012

American White Pelicans at Big Creek in Amherstburg V3

4,5,6...7 American White Pelicans? My first for Ontario. Heavily cropped...

After reading about the reported White Pelicans and Little Blue Heron at Holiday Beach this week, I felt I should go and check it out.  It was reported that the Egret numbers at Holiday Beach/Big Creek might be the largest recorded Egret roost numbers in Canada. This morning, I was unable to find a juvenile Little Blue Heron, as most Great Egrets were very far from the hawk watching tower, and my scope is just not sharp enough to see beak detail to distinguish a LBH from a Great Egret.

Or is this a Juvenile Herring Gull?

Recent walks of Point Pelee beaches gave views of Bonaparte's Gulls and Lesser (?) black-backed Gulls. I was hoping to see a Little Gull, but I haven't convincingly seen one yet. I can't honestly differentiate between a greater and lesser gull at this point, so I usually go by what is more statistically abundant. Ebird charts for Essex County hint that Greater black backed Gulls are much more abundant than Lesser black backed Gulls.

A quick kayak trip into Point Pelee's Marsh resulted in surprisingly low numbers of shorebirds. I was expecting more to be honest. On the various islands of mudflats I saw:
2 Semipalmated Sandpipers
5 Killdeer
1 Juv Spotted Sandpiper
3 Short billed Dowitchers
15 Canada Geese
25 Black Terns (in the Lilypads)

I should enter this into e-bird. I should go out at least one more time into the marsh. Probably in the second week of August.
Any thoughts on the subspecies of this SBD? Hendersoni?

Lots of butterflies around at Point Pelee along west Beach. Common Buckeye and American Snout are very abundant, but Giant Swallowtails, Red Spotted Purples, Viceroy, Monarch, Painted Lady and even Variegated Fritillary. I was hoping to see an Olive Hairstreak this week but dipped.


Good Birding,

Long Dash Skipper? ... Probably Pecks

Sunday, July 22, 2012

Sorting Through Swallows & Some Butterfly Lifers

Tawny Emperor... A Point Pelee Specialty
Over the last week or so, I've been able to get out a few times and rack up a few more butterfly lifers. The best butterfly of the four was found serendipitously. While bringing my son to the tip of Point Pelee, I couldn't help but notice a worn but still beautiful Tawny Emperor (dark phase) on the tram as we were driving! It was on the tram on the way to the tip, and was still on the tram when I went back later on! Tawny Emperors are very rare in Canada. They are best found at Point Pelee or Pelee Island. The southern latitude and generous abundance of Hackberry trees make this a 'common' butterfly at Point Pelee.
Dainty Sulphur. Little, Yellow, Different.
 A recent walk at Hillman Marsh gave nice views of what I think are Dainty Sulphurs. I had read about them on a Ohio-based blog that I follow, and even in Ohio, they are very rare. They are very tiny! I also photographed a nice Fiery Skipper which was exciting. Peck's Skipper was another Butterfly Lifer that I picked up a week or so ago as well. Hillman Marsh was quiet bird wise, with the exception of a generous showing of swallows. 

Another blog that I read from Michigan had some Bank Swallows photographed recently and it dawned on me that I lazily haven't added this bird to my life list. So, its a lazy hindsight lifer that I just never bothered to pick up until now. Cliff Swallows are not really on my 2nd year life list either, so I might be upping my list by two here. Road 19 between Concession C&D has swallows perched on the telephone wires. Bank Swallows, Barn Swallows, Cliff Swallows, Rough Winged, Purple Martins and Tree Swallows are pretty easily seen for anyone willing to sort through them. All-about-birds has a nice write-up on all the swallows at this link: http://www.allaboutbirds.org/guide/browse_tax/31/.

Its pretty cool to think that of the 8 North American swallow species, 6/8 can be pretty easily seen at Point Pelee right now. The other two absent species are Cave Swallows (Texas Resident) and Violet Green Swallows (Western Resident). I lucked out and saw Violet-Green Swallows last year in BC.

Good Birding,

Lifer Summary:
Bank Swallow #303
Cliff Swallow #304

Tuesday, July 17, 2012

Northern Bobwhite at Malden Park

With recent ontbirds postings about Northern Bobwhite at the Dow Wetlands in Sarnia, I had been wanting to drive out there to see it, but couldn't work up the motivation to drive out there (ozone action days). Luckily, an ontbirds posting mentioned Northern Bobwhites at Malden Park, of the Ojibway Complex in west Windsor. Since Malden Park is just minutes from my home, I stopped by Malden Park to see if I could find this awesome bird myself.

With very little effort, I found it this morning on the north end of the park, where the bike path runs along the backyard fences of a row of about 15 or so homes. The bird was seen about near the fourth house from the west-most home. I heard it calling before I saw it. It was calling "White!" without the "Bob-ba" preceding it. Northern Bobwhite is not a lifer for me as I did see it in Florida at the Babcock web reserve. This is my first photo of this bird though!

Note:Northern Bobwhite is a species at risk in Ontario. The link below mentions that harsh winters with lots of snowfall seem to kill off any natural popluations of this bird. Natural populations are basically limited to areas around Walpole Island where Lake Huron flows into Lake St Clair.  This is probably a captive released bird  http://www.rom.on.ca/ontario/risk.php?doc_type=fact&id=110&lang=en

The Green Heron fledglings seem to be doing very well as they were foraging for food this morning. Belted Kingfishers and Spotted Sandpipers were seen as well.
I spotted a Spotted Sandpiper...

My first Android Application- Tickle Tufted Titmouse!

Actual Screenshot from my HTC Sensations 4G phone. I'm running Android 403 (AKA Ice-cream Sandwich)
I picked up a book recently on how to create android apps for touch-screen smartphones. I've had it sitting around for a month or so but finally started reading it yesterday. I read the first 150 pages and created my first app. Instead of petting a kitten and hearing meow, I decided to have a Tufted Titmouse and have it make its call: "Peter Peter Peter".

One app I would like to create is one that might take verbal dictation out in the field, convert it to text and then possibly create a text file (.CSV) that could be uploaded directly to E-bird. That might be too ambitious but its something to shot for. 

Visual IDE environtment of AppInventor. Expereimenting with Speech Recognition

Good Birding!

PS: The wildflower show is about to begin!

Turks-Cap Lily or Carolina Lily ... Ojibway Park Tallgrass Prairie

Tuesday, July 10, 2012

Checkered Skipper and Green Heron Fledglings at Ojibway v2

Common Checkered Skipper (Not Eastern :-)   )

The last two weeks have been super busy for me. Seeing the Rondeau Frigatebird was basically not an option for me. I was hoping it would stick around a little more but maybe it found its way back to the east coast, where it belongs. In March of 2011, I saw a Magnificent Frigatebird flying over my car on Sanibel Island during my lil' birding trip to Florida.

With all the butterfly counts in the last week, it was interesting to read about what was seen and I was reminded about how good Essex County has it with respect to butterfly diversity. A few bloggers mentioned Common Checkered Skipper Checkerspots and that really sparked my interest in finding them myself. A quick check of the Ontario Butterfly Group resulted in some good news: Common Checkered Skipper at Ojibway Park, just minutes from my house... Nice! This butterfly is so rare, that its not even featured in my butterfly guide for Southern Ontario (and it has a rarities section!). I'm not sure if the butterfly I photographed above is a male or female since my photo was not showing enough detail on the edges of the hindwing. According to butterfliesandmoths.org "Upperside of male is blue-gray; female is black. Both sexes have large white spots which form median bands across both wings. Fringes of male checkered but black checks often reach only halfway to edge of fringe." (Butterfliesandmoths.org) See this site for more info in ID'ing the gender of this butterfly.

Here are some others from the last week or two. I saw a Fiery Skipper and Hackberry Emperor recently at Holiday Beach but no photos. Another butterfly I would really like to see is an Olive Hairstreak!

Breeding birds at Ojibway park include Field Sparrows, Eastern Bluebirds , Orchard Orioles, Tufted Titmouse, Indigo Buntings, and so many others. Two that I took note of this week though was this chance find of a Blue-grey Gnatcatcher nest and a Green Heron nest, complete with downy Green Heron Fledglings!

Love this photo. This is what its all about.

Green Heron is one of my *sparkbirds*!

Good birding,

butterfliesandmoths.org, "Common Checkered Skipper", ND, July 10, 2012, WEB, http://www.butterfliesandmoths.org/species/Pyrgus-communis 

Bonus Bird Photos:
Found at Spring Garden area of Ojibway Park

Found at Brunet Park, LaSalle Ontario


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