The 2019 Nonsuch Expeditions “Longtail-Cam” White-tailed Tropicbird chick, fledged and departed out to sea at 8.29am on Monday, the 1st of July, 2019.
“Pig-Pens” parents returned unusually early to Bermuda for this year’s breeding season, first being seen in the beginning of February in the artificial “Igloo” nest # 387 that is installed along the stairway running up from the main dock on Nonsuch Island Nature Reserve where the latest Nonsuch Expeditions Tropicbird Cam was installed this Season.
This nest was installed by a school group as a class project during 2006, and was colonized by a pair of Tropicbirds (Longtails) during the same summer. It produced its first successfully fledging chick in the summer of 2007 since which it has had a very successful record of breeding success, producing successfully fledging chicks in 10 of the last 12 years, with failed breeding only in 2009 and 2016.
This nest, along with over 80 others on Nonsuch Island and a total of nearly 300 nests, at ten study locations around Bermuda, have been monitored and their breeding success recorded every year since 2006 by the Senior Terrestrial Conservation Officer as part of a long-term study of Tropicbird breeding biology and population dynamics on Bermuda.
Over 1500 Tropicbirds have been fitted with identification bands as part of this study, including all 10 chicks that have so far fledged from “Pig-Pens” nest.
For the 2019 breeding season, the adult Tropicbirds from nest # 387 laid their single egg around the 6th of March, one of the earliest records of Tropicbird egg-laying that has been recorded during the study. This egg was incubated by both parents for 48 days, with the chick hatching on Tuesday the 23rd of April. The chick grew rapidly, increasing from 45 grams in weight on the 26th of April, when the first growth check was carried out on the 3-day old chick, to its maximum recorded weight of 560 grams on the 12th of June, when it was fitted with i.d. band no. C1521. This band will enable positive identification for the rest of its breeding lifespan.
“Pig-Pen” was given its last growth check on the 29th of June, 2019, by which time its weight had dropped to 427 grams, and wing chord (outer wing) length had increased to 259 mm. Our Tropicbird chick fledged out to sea 69 days after hatching on the first day of July, 2019, and likely will not return back to the Castle Harbour Islands on Bermuda for several years. Recaptures of Tropicbirds banded as chicks indicate that they first return to choose nest sites and mates at 3 to 4 years of age, and that they generally return if not to the same nesting island, then to one in close proximity. The bill length of “Pig-Pen” seems to indicate that it is a male bird, so we will be looking out for its return to Nonsuch or a neighboring island around 2022-2023.
Jeremy Madeiros | Senior Terrestrial Conservation Officer, Bermuda Dept. of Environment & Natural Resources