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Point count surveys are widely used for monitoring songbird populations, but little is known of the effect of the observer on songbird behavior during point counts. We used a novel, wireless array of recorders to determine the location of singing birds with and without the presence of an observer. The array consisted of seven autonomous recording units synchronized to Global Positioning System (GPS) clocks, set around the perimeter of a 50-m-radius circle with one in the middle. Units were set to record automatically from half an hour before dawn until 10:00 each morning. We sampled 26 different locations in old fields at the Prince Edward Point National Wildlife Area in eastern Ontario between 1 June and 4 July 2007. Position estimates derived from a time-lag cross-correlation algorithm had a mean error of 1.7 m within 50 m and 5.6 m at 100 m from the center of the array. We found no difference in the positions of birds when an observer was present or absent. We also found no difference in the number of individuals or species detected or in the onset of singing. Our results suggest that, at least in the community we studied, observers conducting point counts do not cause significant changes in bird behavior. RESUMEN Los conteos por puntos se utilizan ampliamente para el monitoreo de poblaciones de aves, pero poco se sabe del efecto del observador sobre el comportamiento del ave durante el conteo por punto. Utilizamos una novedosa serie inalambrica de grabadoras para determinar la ubicacion de aves que estaban cantando, con y sin la presencia de un observador. La serie estuvo formado por siete unidades autonomas de grabacion, situados en el perimetro de un circulo de 50 m de radio, con una unidad en el centro. Estas unidades estaban sincronizadas con relojes del Sistema de Posicionamiento Global (GPS). Las unidades estaban programadas para grabar automaticamente desde media hora antes del amanecer hasta las 10:00 de cada manana. Tomamos muestras en 26 lugares distintos en campos viejos del Prince Edward Point National Wildlife Area en el este de Ontario entre el 1 de junio y el 4 de julio de 2007. Estimaciones de la posicion de las aves, derivadas de un algoritmo de tiempo retardado con una correlacion cruzada, tenian una media de error de 1,7 m dentro de 50 m, y de 5,6 m a 100 m del centro de la serie de unidades. No encontramos diferencias en las posiciones de las aves cuando un observador estuvo presente o ausente. Tampoco encontramos diferencias en el numero de individuos o especies detectadas, o en la iniciacion de cantos. Nuestros resultados sugieren que, al menos en la comunidad que estudiamos, los observadores que realizan conteos por puntos no producen cambios significativos en el comportamiento de las aves.

We documented immediate, behavioural responses of Indo-Pacific bottlenose dolphins (Tursiops sp.) to experimental vessel approaches in regions of high and low vessel traffic in Shark Bay, Western Australia. Experimental vessel approaches elicited significant changes in the behaviour of targeted dolphins when compared with their behaviour before and after approaches. During approaches, focal dolphin groups became more compact, had higher rates of change in membership and had more erratic speeds and directions of travel. Dolphins in the region of low vessel traffic (control site) had stronger and longer-lasting responses than did dolphins in the region of high vessel traffic (impact site). In the absence of additional information, the moderated behavioural responses of impact-site dolphins probably would be interpreted to mean that long-term vessel activity within a region of tourism had no detrimental effect on resident dolphins. However, another study showed that dolphin-watching tourism in Shark Bay has contributed to a long-term decline in dolphin abundance within the impact site (Bejder et al., in press, Conservation Biology). Those findings suggest that we documented moderated responses not because impact-site dolphins had become habituated to vessels but because those individuals that were sensitive to vessel disturbance left the region before our study began. This reinterpretation of our findings led us to question the traditional premise that short-term behavioural responses are sufficient indicators of impacts of anthropogenic disturbance on wildlife.

Abstract Nestling growth may be used to estimate age of nestling raptors, which is valuable for investigating hatch order dynamics and nestling behavior, as well as assessing reproductive rate and back-calculating hatching date. To estimate nestling age, the most valuable parameter to measure growth is one that does not vary greatly with environmental factors, and ideally is applicable over a wide range of populations. We measured growth of nestling Red-shouldered Hawks (Buteo lineatus) in Quebec, Canada, from ages 3 days to near fledging (38 days old), and compared growth of several parameters in different size broods. As a validation study, we measured similar parameters one time in known-age nestling Red-shouldered Hawks in southwestern Ohio. Growth rates for tarsus length, bill length, and tail length differed between nestlings in broods of one and three young, respectively, in Quebec. However, mass gain and growth of secondary feathers (mean length of first and second secondaries) did not differ betw...

Understanding bird migration and dispersal is important to inform full life-cycle conservation planning. Stable hydrogen isotope ratios from feathers (δ2Hf) can be linked to amount-weighted long-term, growing season precipitation δ2H (δ2Hp) surfaces to create δ2Hf isoscapes for assignment to molt origin. However, transfer functions linking δ2Hp with δ2Hf are influenced by physiological and environmental processes. A better understanding of the causes and consequences of variation in δ2Hf values among individuals and species will improve the predictive ability of geographic assignment tests. We tested for effects of species, land cover, forage substrate, nest substrate, diet composition, body mass, sex, and phylogenetic relatedness on δ2Hf from individuals at least two years old of 21 songbird species captured during the same breeding season at a site in northeastern Alberta, Canada. For four species, we also tested for a year × species interaction effect on δ2Hf. A model including species as single predictor received the most support (AIC weight = 0.74) in explaining variation in δ2Hf. A species-specific variance parameter was part of all best-ranked models, suggesting variation in δ2Hf was not consistent among species. The second best-ranked model included a forage substrate × diet interaction term (AIC weight = 0.16). There was a significant year × species interaction effect on δ2Hf suggesting that interspecific differences in δ2Hf can differ among years. Our results suggest that within- and among-year interspecific variation in δ2Hf is the most important source of variance typically not being explicitly quantified in geographic assignment tests using non-specific transfer functions to convert δ2Hp into δ2Hf. However, this source of variation is consistent with the range of variation from the transfer functions most commonly being propagated in assignment tests of geographic origins for passerines breeding in North America.

Population declines of farmland birds over recent decades in Europe, Canada and the USA have been attributed to more intensive agricultural management. We counted birds during the 1990 breeding season on 72 field sites in southern Ontario, Canada, paired between 10 organic and 10 conventional farms for local habitat to enhance our ability to detect effects of agricultural practices. Of 68 species recorded, 58 were on organic sites, 59 on conventional. Species richness and total abundance were significantly greater on organic than conventional sites based on log-linear regression. Of 43 species analyzed with log-linear regression, eight (18.6%) were significantly (P<0.05) more abundant on organic than conventional sites and four (9.3%) approached significance (0.05

Review of: Westneat. D. R. and Fox. C. W. 2010. Evolutionary Behavioral Ecology. Oxford University Press, Oxford. 641 pp. ISBN 978-0-19-533192-9. $150.00 (cloth), $49.95 (paper). For more than 30 years, my goal in teaching has always been to make important but sometimes difficult subjects (think statistics, scientific writing) accessible and palatable to beginning students, with entertaining lectures and step-by-step procedures. One of my old professors once told me that fear and loathing are the major impediments to learning, and I agree. The text? books that! chose over the years exemplified that approach (think Alcock's Animal Behavior: An Evolutionary Approach [ Alcock 2009]). and were wildly popular with the students. My course evaluations confirmed the apparent success of that MO, but now that I have read through Westneat and Fox's new Evolutionary Behavioral Ecology (EBE), I am rethinking the way I teach?for good reasons. More on that later. Evolutionary Behavioral Ecology is an edited volume of 31 chapters spanning many, maybe even most, of the topics that com? prise a modern approach to this field of research, each written by 1-3 experts for a total of 78(!) authors. You cannot go wrong with the likes of Westneat. Birkhead, Sinervo. Gardner, Griffith. Ydenbcrg. Healy. Hurd, Queller, Strassmann, Kokko, Pitnick, Hosken. Brooks. Rundle, Sherman, and Sih. to mention only those I know well enough to argue with about their chapters. Chapters are organized into five broad categories: Foundations (history, and the basics of behavior, genetics, development, phylogcny). Deci? sion Making, Ecology of Behavior. Social Behavior. Reproductive Behavior, and Extensions (speciation. genomics, conservation, syndromes, and humans). The chapters themselves are relatively short (mostly <20 pp) but there are lots of them so the book is paradoxically both big (640 pp) and far from comprehensive. EBE is an obvious successor to the "series" of four books on behavioral ecology begun by John Krebs and Nick Davies in 1978: Behavioural Ecology: An Evolutionary Approach (Oxford, Blackwell: 1st ed. 1978: 2nd ed, 1984: 3rd ed, 1991; 4th ed. 1997; hereafter KDl^k respectively). Unlike most other "edi tio s" of books, each one of the Krebs-and-Davies volumes was completely revised?new authors, new subjects, new approaches. KD1 named and defined the field, bringing together ideas and procedures that had been percolating through the research com? mun ty for a decade or more, with all 12 authors acknowledged leaders in their research areas, and most of them quite young. (In EBE, Birkhead and Monaghan provide a wonderful summary of the history of behavioral ecology for those interested in knowing h w this all got started.) I can well remember how exciting and rewarding it was to work through KD1 in a graduate seminar, as every chapter crackled with the promise of new insights that this approach to the study of animal behavior promised. This was a hard act to follow, but the remaining three KD volumes tried to maintain the levels of novelty and leadership by introducing new ideas, while maintaining the same basic format. KD4, for example, had only 5 of the 16 authors from KD3, and only 3 4 of the chapters on similar topics. Continuing in this tradition, EBE a only two of the authors (Sherman and Birkhead, both writing on different subjects this time) from the 26 who wrote KD4, and at least a dozen brand new topics. For almost three decades, KD 1-4 were the staple of graduate seminars, continu? ally defining, summarizing, and shaping the field. Because each of Krebs-and-Davies volumes was so different, no savvy behav? ioral ecologist could really afford to be without all of them?an excellent, but presumably unintended, marketing ploy. To satisfy th need for a more basic undergraduate text. Krebs and Davies

The interaction of aerial predators and migrant Semipalmated Sandpipers (Calidris pusilla) was studied at Mary's Point in the upper Bay of Fundy, New Brunswick, Canada, during August of 2009 and 2010. Peregrine Falcons (Falco peregrinus) were locally reintroduced and increased from one active nest site in 1989 to 27 in 2010, which coincided with a decline of sandpipers roosting at Mary's Point from an annual mean of 161,000 in 1976â€"1982 to 15,000 or less during this study. Mean roosting time of flocks was 33 min (range = 10 to 40 min; N = 6). Sandpipers returned to the beach 1 h:36 min after high-tide (range = 1 h:10 to 2 h:13 min; N = 5), but were soon flushed again by falcons. On ten of 19 days, during part of the high-tide period, flocks of sandpipers remained in flight over the ocean. Termed Over-Ocean Flocking (OOF), this behavior was seen on days when spring tides inundated all beach habitat, and also at lower tides, which supports the hypothesis that OOF is an antipredator strategy intended to avoid surprise attacks by falcons near the shore. Raptors sighted during 128 hours afield included 226 Peregrines, 20 Merlins (Falco columbarius) and two Sharp-shinned Hawks (Accipiter striatus). At 1.0â€"3.2 Peregrine sightings/h-1 (mean 1.8) the level of disturbance is high and supports the hypothesis that the decline in roosting sandpipers at Mary's Point is linked to predation danger.