Event Statistics - Looking into the Numbers

I don’t tend to keep lists. I do however write up a species list of each type of bird seen and heard during the guided events, which I then send to the attendees. These lists are growing into quite a repository of information and I have looked into the data on the events between May 2019 and February 2020.

In 25 guided walks a total of 133 bird species had been seen and heard. In fact, of these 133 species, only 1 was heard and not seen at some stage, with that being the crossbill. This past winter has proved challenging in tracking down these unique birds. Over the 25 walks there was a mean species count of 47.76, although I’m not too sure which species counts as three quarters of a bird. The median count is 51, and the mode 54.

Over 50 species were recorded on 14 out of the 25 events, and all of these were at coastal sites. Limiting the data to coastal sites only we see 19 events with a mean species count of 52.42, highlighting that a greater variety of species are usually to be found by the coast.

Bearded tits were seen many times at Farlighton Marshes. This view of a stunning male in January 2020 was quite special.
Photo courtesy of Les Phillips.

The highest total of species recorded on one event was 61 at Farlington Marshes in the autumn of 2019. The lowest total was recorded on a windy day in a woodland site and was 26, although on that day 2 immature goshawks were interacting with up to 8 ravens which more than made up for a lower total!

This hawfinch was seen on a guided walk in November 2019. We have had regular
sightings of this species throughout the winter at events in woodland.
Photo courtesy of Les Phillips.

Raptors were well represented and 10 of the 15 breeding species in the UK were seen. I very much enjoy watching birds of prey and some fascinating behaviours such as a marsh harrier mobbing an osprey, merlins hunting and goshawks displaying were definite highlights.

A female merlin taking a rest on a distant mound between hunting flights.
Photo courtesy of Les Phillips.

Wading birds are also among my favourites, I could well say that about most species mind. 22 different types of wader were recorded. They tend to be daunting to beginner observers but with time the majority become distinct in the minds eye. Areas with wading birds often attract other species as well, one such area is Fishbourne Channel where a great mix of waders, ducks and grebes had been seen.

Slavonian grebe seen at Fishbourne Channel in December 2019. Photo courtesy of Les Phillips.

With 62 species recorded on the first event in March 2020, thus already exceeding the highest total from the previous events, I may well have to revisit this after the next 25 events!

- Hugh Baggaley