We will trap, weigh, band, and release male and female lesser scaup throughout the spring stop-over period at Pool 19, using standard techniques (Haramis et al. 1982, 1987; Pace and Afton 1999). We will select a sub-sample of 17 females, with minimum body mass of 650 g and maximum expected body mass of 900 g (Anteau 2006), to be implanted with 38 g, intracoelomic satellite transmitters (PTTs; see below).
All PTTs will be tested for successful satellite transmission and confirmed to be working prior to implantation. We will use PTTs identical to those that have been used successfully in lesser scaup captured and radio-marked in the Great Lakes region (Badzinski and Petrie 2006). We will implant PTTS in females within the range of body mass of those successfully radio-marked in the Great Lakes region (Scott Petrie, personal communication). Finally, we will use a PTT duty cycle that theoretically will provided locations every 1.4, 7.2, and 3.3 days during spring migration, on breeding and wintering areas, and during fall migration, respectively. Theoretical battery life will allow potential coverage during 2 spring migration periods for each radio-marked female.
Click here to view pictures of the 2008 scaup banders
Click here to view pictures of the 2009 scaup banders
Surgical Implant Procedures
Dr. Mark Mitchell, who is experienced in implanting PTTs in ducks, will conduct all implant surgeries at the field site. The ducks will be anesthetized using isoflurane. Initially, the anesthesia will be delivered by facemask (5% isoflurane, 1 liter oxygen flow rate). Once females lose consciousness, they will be intubated using a 3-0 to 4-0 endotracheal tube. The ducks will be maintained at 2-3% isoflurane at a flow rate 1 liter of oxygen. The birds will be positive-pressure ventilated during the procedure every 10 seconds. A pulse oximeter will be used to monitor heart rate.
The ducks will be surgically prepped at two sites: the dorsal synsacrum at the junction of the spine and pubis and the ventral abdominal muscles. The dorsal site will be done first. The sterile surgical preparation will be done using a 1% betadine solution and sterile saline. Once prepped, the surgical site will be covered with a sterile 2 x 2 gauze pad. The duck will then be placed in dorsal recumbency to prep the abdomen. The same sterile technique will be used. A clear surgical drape will be placed after the surgical prep is completed. The ventral abdominal incision will be made through the skin and rectus abdominis using a #15 scalpel blade. Once the coelomic cavity is opened, the right abdominal airsac will be manually deflated.
The antenna of the PTT will be placed into a blunt trochar and digitally guided through the incision (around the viscera) to the point of the pubic/spinal juncture. Using gentle pressure, the trochar will be advanced through the skin and out the dorsum of the bird. The entire trochar and antennae will be extracted sterilely (by manipulating it through the clear drape) out of the body cavity.
The PTT then will be digitally manipulated into place along the right body wall. The incision in the body wall will be closed using 4-0 PDS using a simple continuous pattern. The skin will also be closed with 4-0 PDS using a simple continuous pattern. A single 4-0 PDS suture will be used to anchor the antennae to the skin on the dorsum of the bird. The birds will be recovered on room air using an ambubag. Once the females have regained their righting reflex and have been extubated, they will be held in a warm, quiet area for 2 hours prior to release at the original capture site.