Aerial surveys in January 2017 of the rufa Red Knot (Calidris canutus) population wintering in Tierra del Fuego, South America, revealed a total of 13,127 birds. This is approximately 15% higher than the number recorded in January 2016 (11,150), though still within the range observed during 2011-2015 (10,000-14,000 birds). While the population is not showing any signs of a sustained recovery (there were 50,000 birds as recently as 2000), at least this increase is a promising sign.
In 2017, nearly all the knots counted were found in Bahia Lomas, Chile (99.8% of the birds occurring in Tierra del Fuego). At the other major historical wintering area in Rio Grande, Argentina, the situation continues to deteriorate, with only 27 rufa Red Knot counted during the survey. Counts at Rio Grande were in the range of 3,000 to 5,000 birds as recently as 2008, but have fallen dramatically since then. The concentration of nearly all the Red Knot in one location (Bahía Lomas), and in one major flock, makes them particularly vulnerable to any environmental problems that might occur locally.
Flock of Red Knots as seen during the aerial survey. Photo: Antonio Larrea.
Bahia Lomas and Bahia San Sebastian (part of the Costa Atlántica de Tierra del Fuego WHSRN Site) are both major wintering areas for Hudsonian Godwit (Limosa haemastica). The 2017 aerial surveys recorded a total of 24,900 godwits, 808 more birds than in 2016, with this increase in Bahía San Sebastian (numbers in Bahía Lomas remained the same between years). The 2016 and 2017 survey totals represent the lowest on record for the species in this area since 1982, and the population appears to be declining, especially since 2004.
The 2017 surveys were conducted by Guy Morrison, Susan Morrison, Antonio Larrea and Jocelyn Velasquez, with the support of the pilots Federico Macini (Chile) and Santiago de Larminat (Argentina). Both the 2016 and 2017 surveys had a focus on training local biologists in aerial survey techniques through theoretical and practical exercises, in addition to validating the accuracy of the aerial counts through simultaneous photographs of flocks.
The survey team, from left to right: Dr. Guy Morrison, Mrs. Susan Morrison, Capt. Federico Macini (pilot), Sra Jocelyn Velasquez (ENAP), Sr. Antonio Larrea. The survey was conducted in the helicopter provided by ENAP (Chile’s National Petroleum Company) – Eurocopter model EC135. Photo: Antonio Larrea.
The surveys were made possible thanks to the Bobolink Foundation in support of the Atlantic Flyway Shorebird Initiative, and through a helicopter provided by ENAP (Chile’s National Petroleum Company).
