PRRIP 2008-2009 Interior Least Tern and Piping Plover Monitoring and Research Report

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We re- visited each site 2 -3 times between banding and fledging to re -sight banded birds. We obtained band combinations of piping plover chicks by visually scanning brood - rearing areas from a distance to minimize bird disturbance. Due to the sedentary behavior and posture of interior least tern chicks, re- sightings required us to pick chicks up to read color band combinations. We visually scanned areas where interior least tern chicks were previously located and conducted searches on foot to locate and capture banded chicks; handling time was <5 minutes per re- sighting. RADIO TELEMETRY Interior least tern and piping plover adults were fitted with radio transmitters primarily in support of objective 1, but also provided information in support of objectives 2--4. We attempted to apply radio - transmitters to 16 interior least tern and 16 piping plover adults. Transmitters were placed on 1 bird per pair. For interior least terns, we used leg -band mounted transmitters, consisting of a <l.lg transmitter (Holohil BD -2) secured to a lA aluminum leg band with nylon thread. The leg band transmitter package was fitted on the upper leg, and was the only metal band applied to radio - marked interior least terns. We placed 1 -3 smears of an indelible Sharpie /Marks -a -Lot marker (black, brown, blue, green, or red) on radio - marked interior least terns under the wings, on the side of the breast, or near the vent to indicate nesting colony and facilitate relocation of individuals from colonies during behavioral observations. For piping plovers, we used —1.2g, glue -on transmitters (Holohil BD -2G) attached with cyanoacrylate glue to the intrascapular region of the bird. All radio - marked birds were released adjacent to the colony within 10 minutes of capture and we observed the birds to document resumption of normal behaviors (e.g., incubation & foraging). We used automated dataloggers to document presence /absence of radio - marked birds. We used automated data collection computers (ATS R4500S Scientific Receiver/Datalogger connected to >_ 1 Yagi antenna), which was programmed to scan all deployed frequencies every 5 -10 minutes. All equipment (loggers, receivers, and antenna) was housed in blinds so they did not provide a perch for raptors or other birds. The dataloggers recorded the presence of radio - marked birds, which we correlated with direct behavioral observations and used to develop estimates of trip frequency and duration by pairs and colonies. Dataloggers and blinds were positioned strategically to provide meaningful records of bird -use of target habitats and to allow us access to the dataloggers 2 -3 times /week without disturbing nesting or foraging birds. We also used hand- held Yagi antennas to locate birds in foraging areas during behavioral observations. BEHAVIORAL OBSERVATIONS Behavioral observations were conducted in support of objective 2 and provided information on locations where sampling was needed for objective 3. We observed the behaviors of interior least terns and piping plovers to identify the proportion of time spent foraging, estimate the rates of foraging behaviors and habitats used for foraging piping plovers, and determine success rates of foraging interior least terns. Behavioral observation sessions occurred during 4 -hr intervals (0600 -1000, 1200 -1600, and 1700- 2100h). We systematically allocated sessions to ensure we observed each interior least tern and piping plover pair at least 1 time during each interval every two weeks. We recorded the number of active nests and broods in the area for each species during each session. For colony sites, this was the number of known nests within the colony, not just the number visible from a behavior data collection location. For non - colony locations where PRRIP 2008 -2009 Tern /Plover Report Page 28 of 42