Friday, February 9, 2007

Chile - Chiloe Island - February 7, 2007

With a good catch of Hudsonian Godwits, we had satisfied one of the goals of the Chiloe part of our expedition. Whimbrels proved to more elusive. Problems arose with our two small cannons that threw relatively light projectiles which lost momentum quickly when fired into the wind, even if the wind was not very strong. They were of a different design to those we now use in the US, weighting far less, with less power even though they use more powder. Six years ago, we took these cannons to Chile because they were lighter and easier to transport. But the lack of weight means less momentum to carry the net. We tried to overcome this disadvantage with more gunpowder, but at one site here in Chiloe we could only position the net so that it fired into the (moderate) wind. Each time we fired on a decent catch of Whimbrels, most escaped as the net almost froze in the air and drifted back under the pressure of the wind. After two attempts at the Caraco site on Monday and Tuesday we caught only 18 Whimbrels. We decided to try a new site and a new technique.

On Thursday, we moved back to the Pullao site where we caught godwits previously. The extensive mudflats lie below lush fields and are dotted with the occasional cow, pig or sheep roaming freely right out onto the mud. Over 6,000 godwits and 200 Whimbrels used the site a few days ago, now the Whimbrels remained at similar numbers, but the godwits were down by half. We decided to use the big net with three cannons: two with the light projectiles and one of the heavier, more powerful cannons we normally use on the Delaware Bay and which we brought from NJ so that we could fire this net. The small net is 104 sq yards (13 x 8) and the big net is twice the size (220 sq yards: 22 x 10), so it needs much more power. With the big cannon in the center and the two small cannons on either side and with 20% more powder, we hoped that the net would be fully extended when it was fired. We also hoped that the small cannons would stand up to the heavier charge.

They did! We chose our site well and within 30 minutes we had a catch, but with birds in the danger zone, the two yard wide area immediately in front of the net. The birds were jittery and repeatedly flew from our beach but returned, after some judicious twinkling by Mark, Jim and Luis, always moving right up to the danger zone. At last we fired and caught 78 Whimbrels and one American Oystercatcher. Our banding crew, Mandy, Humphrey, Mark, Jim, Brad, Jorge, Daniela, Gabriel, Luis and I, fully processed the birds in good time yielding all the data necessary for Jim and Brad’s study.

This was the final field day of our 2007 Bahia Lomas/ Chiloe Island Expedition. We accomplished all of our original goals. Sufficient birds were caught in both locations for all the studies taking place or about to start. We completed counts at Bahia Lomas allowing between-year comparison of numbers. We helped Carmen continue work on the benthic invertebrates and foraging of Red Knots and Hudsonian Godwits and expanded it to include mussels. We transformed the idea of a small researchers’ hut on Bahia Lomas to a more ambitious “Tierra del Fuego Bird Observatory” and secured local support. Finally we enabled the Nature film crew to overcome the difficulties presented by the harsh environment and low bird numbers to complete their filming. In Chiloe, Jim and Brad can begin the genetics study they had been planning but unable to start.

After all was done, we were within an hour of leaving for Puerto Montt and the long trip home, when Daniela and Jorge treated us to Chorante / Curranto, a traditional holiday meal of the Chiloe Islanders, consisting of mussels, clams, chicken, smoked pork ribs, sausage, potatoes, fresh peas, tomato and onion salad and salsa. The meal took the entire morning to prepare. We left with full stomachs and warm hearts for our hosts and all the other Chileans who had done so much to make our work possible.


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