One of the big problems with cryptic species is that they are just that – cryptic! When COG was surveying for the then proposed site for the National Museum at Yarramundi Reach, which I assisted in, I asked if anyone bothered to check the reed beds for Little (now Black-backed) Bitterns. When told “NO” I proceeded to wade chest deep through the reeds and successfully flushed a couple. Since then there have been quite a few records, often by people using canoes to scan the lake side edges of the reeds. Looking at Lake Ginninderra and the creek that flows into it (past the Crace and Giralang ponds and close to the large McKellar pond where the two current species are being recorded), there are large expanses of reeds that could easily hide both species of bittern and that theoretically are inaccessible except y boat.
I don’t know about the south side of town but in the newer Gungahlin suburbs there are numerous small reed and rush-lined ponds that would be quite capable of hosting both bittern species. How many people visit these on a regular basis? I don’t always agree with Philip but I think he is right in this case, with most of the records being of the same birds being constantly reported by people seeing them for the first time and putting them on the chat line. How many make it to the Rarities Panel I don’t know but all records of these species should go through the panel to make sure they are officially recorded as well as putting in something like an “incidental report form” which can be found on the COG website.
Mark
Thanks for that. So mainly a warm month visitor. (The first RAOU Atlas suggests that too, the second RAOU Atlas is hard to perceive any trend). So is the current winter record record unusual? It does beg the question though about counting the number of records by month. Are these separate records? How real are these data in terms of the species presence? In this species I perceive that there would be very few separate events. The species is rarely here and when here many people go to find it. So there may well be a lot of recounting of the same birds in this graph. Which can make a trend look bigger than it should.
-----Original Message----From: Wallaces [m("bigpond.net.au","skcbf");">] Sent: Thursday, 12 June 2014 12:48 PM To: 'canberrabirds' Subject: RE: [canberrabirds] Little Bittern
Previous records of Australian Little Bittern are all from October to March. The graph below shows the number of records by month for the period 1 July 1981 to 30 June 2013.
Steve
