Posted | filed under Weekly Reports.

It has been a slow week at the Lesser Slave Lake Bird Observatory as we pass the peak in songbird migration. Only a handful of species are still moving, including Cedar Waxwings, Mourning Warblers, Alder Flycatchers, and Red-eyed Vireos.

While most of our time is spent watching the skies and forests to document movements, the mist-nets are an important part of our monitoring protocols. These nets let us capture a subsample of songbirds to take measurements, estimate their age, and mark them with a unique nine-digit number on an aluminum band.

Above: This Ovenbird was banded in 2014 and is now 10 years old!

This week’s highlight was capturing a banded Ovenbird whose band number I did not recognize, meaning this bird was either exceptionally old or banded by another researcher. Upon consulting our databases, we discovered that it was one of our own bands from way back in July 2014. Since it was hatched the year before, this Ovenbird is now 10 years old and just shy of the longevity record for Ovenbirds of eleven! We have recaptured this bird seven time since we banded it: twice in 2014, once in 2017, twice in 2019, once in 2020, and most recently on May 26, 2023. These previous recapture records suggest that this is a female who will soon be nesting and incubating another brood.

Recapturing a bird we have banded is not unusual at our station since a songbird can return to nest within 10 m of where it successfully nested last year. On average, we recapture 6-10% of the birds we band per year. These internal recaptures provide important data on stop-over rates, year-to-year survivorship, local breeding activity, and can suggest how long these natural wonders may live despite traveling thousands of kilometers over dangerous terrain every year. It is extremely uncommon, however, for one of our banded birds to be found outside our study area.

Above: Female Northern Saw-whet Owl we banded last fall is now nesting near Sherwood Park. Photo curtesy Brett Bodeux.

Yet, we were also lucky enough to be notified of one such recovery. On May 6, 2023, researchers northeast of Sherwood Park recaptured a Northern Saw-whet Owl we banded last fall. She was already sitting on eight eggs, which is certainly an overachievement for this species. Indeed, this is the most eggs these other researchers have seen in a clutch since they started their nest box monitoring program in 2016.

Above: Approximate location of the most recent band recovery in our new map.

This discovery is only the 44th bird of nearly 106,000 birds we have banded to be found again outside our own programs. That means just 0.05% of our bands have been rediscovered elsewhere. Despite how rare these reencounters are, they provide incredible data about potential migratory routes or even rates of travel. If you would like to explore this amazing data of both birds banded by us being found somewhere else and where we have received bands birds from, be sure to check out our new interactive encounter map.

Found a banded bird? Make your contribution to avian research at:

By Robyn Perkins, LSLBO Bander-in-Charge