Tuesday, October 25, 2011

Marsh Monitoring Program: Survey Says!

Earlier this year, Jean and I volunteered to assist with the Great Lakes Marsh Monitoring Program. The MMP is a cooperative program of Bird Studies Canada, Environment Canada and the
U.S. Environmental Protection Agency. We had selected a marsh in St. Catharines to survey for the program and our first of three visits to the spot, marked as Barnesdale Marsh 2, was on June 4.

It was a cool and cloudy morning but there was no threat of rain and it was warm enough (at least 16 degrees Celsius) to conduct the 15 minute survey. The 15 minutes consists of two 5 minute passive (silent) observation periods separated by one 5 minute call playback period. We were provided with a MMP Broadcast CD that has a 15 minute running time with prompts to indicate different components of the survey.

I estimated the overall size of the marsh as tiny (between 1.5 and 2.5 hectares), so we only had one station to survey along the route. If we had additional stations, they would have to be separated by at least 250 metres for the marsh bird survey and at least 500 metres if we were doing an amphibian survey.

The survey was conducted from a central point located on a 100 metre semi-circular sample area. Looking to the southwest, the sample area covered the entire width of Richardson's Creek as well as the tree-covered bank on the opposite side of the creek.

So, what were we looking for? Individual birds were marked in one of four categories: focal species, secondary species, aerial foragers or outside/fly-throughs. Focal species were the priority which included American Bittern, American Coot, Black Rail, Common Moorhen, King Rail, Least Bittern, Pied-billed Grebe, Sora, Virginia Rail, and Yellow Rail. Focal species are surveyed at an unlimited distance.

Secondary species, basically species not listed as a focal species, are only counted, recorded and mapped if observed within the 100-m station area.

Birds seen actively foraging in the air within the survey station area are recorded as aerial foragers. Tree Swallows picking insects out of the air and a Belted Kingfisher diving to the water's surface are examples of aerial forgers.

Outside/Fly-throughs include additional secondary species observed outside the station area and birds (focal or secondary) that fly through the survey station without landing or foraging during the 15 minute survey.

For the survey, only one person can find, identify, and count the birds. That was Jean's job. I was the assistant, the lucky one to carry the broadcast unit down the slope to the creek's edge and document information. More than one observer would bias the results.

What did we find during our first visit? No focal species were seen or heard. Secondary species mapped included Red-winged Blackbirds, Baltimore Oriole, Great Blue Heron, a pair of Wood Ducks (FOY) and a Ruby-throated Hummingbird. At first it appeared the hummingbird would be recorded as a fly-through but it came to a rest near the focal point. It seemed it was conducting it's own survey as it sat perched on a small branch above the creek. A Mourning Dove was recorded on the Outside/Fly-throughs list.

The weather was warmer and there was no cloud cover during the second visit.

Red-winged Blackbirds, Great Blue Herons (3) and a perched Belted Kingfisher were observed within the survey area. Barn Swallow, Tree Swallow and American Goldfinch were fly-throughs.

No ticks on the focal species chart. Would a third time be a charm?

Though it was not essential, we conducted a third survey of the Barnesdale Marsh on Canada Day (July 1). One last attempt to record a rail or bittern but the calls broadcasting from our boom box were unanswered.

Since 2006, Jean and I have birded this little area adjacent to a residential neighbourhood in Port Dalhousie a number of times between the months of March and October. Despite not finding any focal species during the MMP or on my eBird lists for this spot, we will return to Richardson's Creek for the program in 2012. As stated in the participant's handbook, surveys of small marshes are needed to help determine the effects of marsh size on species diversity and abundance. If we can observe this many turtles in such a tiny marsh, perhaps there's still hope for a bittern sighting.

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