First Two CahowCam Chicks Have Returned!

Both "Backson" from 2013 and "Lightning" from 2014 have returned after surviving the odds of their first few years alone at sea.

Even more incredibly Backson, now confirmed to be a female has laid her first egg with her mate in a nest that they have been prospecting in Translocation Colony B on Nonsuch Island.

Jeremey Madeiros | Returns of 2013 and 2014 “CahowCam” Cahow Chicks

The present 2017-2018 Cahow breeding season has already produced a number of surprises and developments in the Recovery Program for Bermuda’s critically endangered National Bird, the Cahow or Bermuda Petrel, one of the rarest seabirds on Earth.

Since 2013, the team has been video monitoring one of the deep Cahow nest burrows on the Nonsuch Island Nature Reserve, to help fulfill one of the primary objectives of the Cahow Recovery Program, that of public outreach and education.

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In 2013 an infrared video "CahowCam" (developed by LookBermuda as part of the Nonsuch Expeditions) was installed for the first time in the R832 Cahow burrow at the “A” Cahow colony on Nonsuch Island. This chick hatched on the 13th of March, 2013, and developed normally over the next 3 months, reaching a peak weight of 393 grams on the 6th of June. It then rapidly developed its adult feathers and carried out 6 nights of pre-departure exercising activity, coming out of the nest burrow at night to exercise and strengthen its flight muscles and imprint on the nest colony site. During this period, it “slimmed down” to a normal departure weight of 293 grams, fledging out to sea on the night of 16th June, 2013. The chick was then not seen for several years, living out on the open ocean and learning how to find and catch food, avoid predators, and learn how to survive on one of the harshest environments on Earth; the North Atlantic Ocean.

Over 4 years later, on the 5th December, 2017, I was carrying out a check of nest burrows at the “B” nesting colony on Nonsuch Island. This second site has had Cahow chicks translocated to it since 2013, in an effort to establish a second nesting colony on the island, following the success of the first, “A” colony. Earlier, on October 30th, one of the nests at this second site was prospected for the first time, with a male Cahow found in it that had been translocated to this site in 2013.

On this day, I could see a Cahow in the burrow that had already begun building a grass nest, and when captured and brought out of the nest for examination, I could see that it was one of the birds that I had previously banded as a chick. The band number, E0500, also seemed oddly familiar, so I checked my records and confirmed that this bird was indeed Backson, our first CahowCam video star! It was very satisfying to see that Backson had not only survived its risky adolescent period at sea, as typically only about one-third of fledging Cahow chicks survive this period to return as adults, but that it had already paired up with another Cahow.

Normally, new pairs of Cahows do not produce eggs during their first year together, but on the 22nd January, 2018, I found Backson incubating a newly laid, fertile egg in this nest burrow. I was also able to confirm for the first time that Backson was indeed a female. As of this time, we are just waiting to see if this egg hatches, which would happen in the next two weeks or so.

As if all this was not exciting enough, on the 20th January, 2018, I had discovered another newly returned Cahow, prospecting inside a nest burrow on one of the original small nesting islets. Upon examination of its band number, this bird turned out to be the second CahowCam chick, which was named “Lightning” by Sophie Rouja in the 2014 nesting season. This bird, from the R831 nest on Nonsuch Island, hatched on March 2nd, 2014, reached a peak weight of 422 grams on May 6th, and fledged to sea on May 27th, 2014. (This bird’s name was prophetic, as the CahowCam was knocked out twice by lightning strikes on Nonsuch Island while the chick was developing, which has led to a fair weather naming policy). So far, this bird has not attracted a mate to its new nest site, but we will continue to monitor for new developments in this regard as the season progresses.

Jeremy Madeiros, Senior Terrestrial Conservation Officer, Dept. of Environment and Natural Resources