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K.L. Pardieck

Publications and source records attributed to K.L. Pardieck.

5 recordsLinked to original sources

The 1999-2003 Summary of the North American Breeding Bird Survey

Data from the North American Breeding Bird Survey were used to estimate continental and regional changes in bird populations for the 5-yr period 1999-2003 and the 2-yr period 2002-2003. These short-term changes were placed in the context of population trends estimated over the 1966-2003 interval. During 1999-2003, 41% of all species exhibited positive trends over the entire survey area, while 64% of all species exhibited positive change between 2002-2003. The continental and regional percentages of species with positive trends were also analyzed for 12 species groups having shared life-history traits. Survey-wide for the entire survey period, grassland birds exhibited the lowest percentage of increasing species (14%), with their sharpest declines occurring in the West during 1999-2003 (10% increasing). During 1999-2003, short-distance migrants experienced significant declines in all regions, where numbers of species with increasing trends ranged from 22% - 34%. Most species fared well during the 2002-2003 period, with 64% (P < 0.05) increasing survey-wide. This was primarily a result of increases in the Central and Western BBS regions where 21 of 24 species groups exhibited significant increases in the number of species with positive trends.

Bird Populations

Population trajectory of burrowing owls (Athene cunicularia) in eastern Washington

Anecdotal evidence suggests that burrowing owls have declined in Washington. The Washington Department of Fish and Wildlife is currently conducting a status review for burrowing owls which will help determine whether they should be listed as threatened or endangered in the state. To provide insights into the current status of burrowing owls (Athene cunicularia), we analyzed data from the North American Breeding Bird Survey using two analytical approaches to determine their current population trajectory in eastern Washington. We used a one-sample t-test to examine whether trend estimates across all BBS routes in Washington differed from zero. We also used a mixed model analysis to estimate the rate of decline in number of burrowing owls detected between 1968 and 2005. The slope in number of burrowing owls detected was negative for 12 of the 16 BBS routes in Washington that have detected burrowing owls. Numbers of breeding burrowing owls detected in eastern Washington declined at a rate of 1.5% annually. We suggest that all BBS routes that have detected burrowing owls in past years in eastern Washington be surveyed annually and additional surveys conducted to track population trends of burrowing owls at finer spatial scales in eastern Washington. In the meantime, land management and regulatory agencies should ensure that publicly managed areas with breeding burrowing owls are not degraded and should implement education and outreach programs to promote protection of privately owned areas with breeding owls.

Northwest Science

The 1995-1999 Summary of the North American Breeding Bird Survey

Data from the North American Breeding Bird Survey were used to estimate continental and regional changes in bird populations for the 5-yr period 1995-1999 and the 2-yr period 1998-1999. These short-term changes were placed in the context of population trends estimated over the 1966-1999 interval. During 1995-1999, 44% of all species exhibited positive trends over the entire survey area, while 44% of all species exhibited positive trends during 1998-1999; neither of these percentages differed significantly from 50%. The continental and regional percentages of species with positive trends were also analyzed for 12 species groups having shared life-history traits. Survey-wide for the entire survey period, grassland birds exhibited the lowest percentage of increasing species (19%). However, during 1995-1999 the declines were less extreme in the Central and Western BBS regions, with 49% and 36% of species increasing in these regions. Neotropical migrants continued to fare better than grassland birds in all regions, although in the Eastern BBS region only 30% of neotropical species had increasing trends during 1995-1999.

Bird Populations

Surveys of Puerto Rican screech-owl populations in large-tract and fragmented forest habitats

We conducted road surveys of Puerto Rican Screech-Owls (Otus nudipes) by playing conspecific vocalizations in secondary wet forest and fragmented secondary moist forest in rural areas of eastern Puerto Rico. Six paired surveys were conducted bi-weekly beginning in April. We recorded number of owl responses, cloud cover, wind speed, moon phase, and number of passing cars during 5-min stops at 60 locations. Owls responded in similar numbers (P > 0.05) in both habitat types. Also, we detected no association with cloud cover, wind speed, moon phase, or passing cars.

The Wilson Bulletin

Evaluation of three elevated mist-net systems for sampling birds

Three light-weight, low-canopy mist-net systems were developed and tested in dry tropical scrub, mangrove and forest habitats. One plastic (polyvinyl chloride) and two aluminum pole systems (with and without pulleys) were used to support mist nets to heights of up to 7.3 m. Although the aluminum telescoping-pole system (without pulleys) was expensive initially ( 79-141/unit (US)), its use reduced capture of nontarget species and may have increased capture of target species when compared with ground-level netting. In one year, its use also reduced labor costs by 756, which completely offset the higher cost of the aluminum telescoping-pole system when compared to the plastic-pole system ( 19/unit). Unlike the plastic-pole system, the aluminum telescoping-pole system was adjustable to any height within its range of 1.8 to 7.3 m, was 1.5 m higher, was more efficient to operate in the field, and was easily moved to new locations. For capture of psittacines, the pulleys of the aluminum telescoping-pole system were not necessary, but their use may assist in efficiently retrieving large numbers of birds from the nets. The aluminum telescoping-pole system was efficient in capturing psittacines, columbids, passerines and possibly chiropterans in habitats with canopies lt 10 m or in the forest subcanopy.

Journal of Field Ornithology