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For federally listed species such as Least Tern Sternula antillarum and Piping Plover Charadrius melodus, correct determination of nest fates and causes of nest failure is crucial for understanding population dynamics and improving monitoring programmes. We used video cameras to evaluate nest fate misclassification rate and to identify factors that may cause researchers monitoring nests at different intervals to classify Least Tern and Piping Plover nest fates incorrectly. During the 2013–2015 breeding seasons, we installed miniature surveillance cameras at 65 of 294 Least Tern and 89 of 551 Piping Plover nests under observation on the Missouri River in North Dakota. Nest fates were assigned in the field from remains found at the nest‐site and then again by an independent researcher who reviewed camera footage. We used ordinal logistic regressions to examine whether monitoring interval, clutch age or temporal factors influenced a correct, partially misclassified (probable successful in the field vs. successful by camera) or misclassified nest fate classification. During a 7‐day monitoring interval between visits, 45% of nests were partially and 27.5% were fully misclassified. The percentage of partially (20%) and fully (8.0%) misclassified nests decreased with a more intensive (3‐day) monitoring schedule. Researchers were also less likely to correctly classify nest fates for Least Terns than for Piping Plovers, and as clutch age and monitoring interval increased for both species. Furthermore, causes of failure (e.g. predators, weather) as determined from field evidence vs. video disagreed for 53.5% of nests. The ability to identify accurately nest fate and cause of nest failure will facilitate a better understanding of factors that limit productivity and will lead to better informed management decisions for improving nest survival. [ABSTRACT FROM AUTHOR]

Avian females with food limitation or are unable to meet nutritional requirements could result in negatively influenced egg size, nest initiation date, nesting season duration, and clutch size. Northern bobwhites Colinus virginianus serve as an adequate model species for supplemental feeding studies because of prolific nesting and re-nesting behavior. We monitored females on treatment and control units to determine if food supplementation influenced: 1) nest initiation, nesting duration, and nesting attempts, 2) nesting success, and 3) egg volume and clutch size. We radio-marked 196 female bobwhites during the breeding season of 2011 and 2012. Hens with access to supplemental feed produced 0.86 and 1.60 nest per hen while hens on control sites produced 0.15 and 0.81 nest per hen during the 2011 and 2012 nesting season, respectively. Average nest initiation varied slightly between treatment and control; though, average nesting season length was 16 and 31 days longer on treatment units. This benefit indicates females with access to food supplementation were in better physical condition compared to females on control units. However, nest success (β = -0.03, SE = 0.40), clutch size (t = -0.37, p = 0.70), and average intra-clutch egg volumes (β = -0.06, SE = 0.20) (t = 0.50, p = 0.61) were unaffected by food supplementation. Total net productivity estimates showed more chicks per hen were produced on treatment sites [Ṗ = 2.34, SE = 0.04 (2011); Ṗ = 5.75, SE = 0.12 (2012)] than control units [Ṗ = 0.61, SE = 0.001 (2011); Ṗ = 3.47, SE = 0.13 (2012)]. Our results suggest that bobwhites with access to supplemental feed broadcast into roadside vegetation throughout the breeding season can potentially increase nesting attempts which may result in increased production and offset population fluctuations due to drought conditions. [ABSTRACT FROM AUTHOR]

Avian females with food limitation or are unable to meet nutritional requirements could result in negatively influenced egg size, nest initiation date, nesting season duration, and clutch size. Northern bobwhites Colinus virginianus serve as an adequate model species for supplemental feeding studies because of prolific nesting and re‐nesting behavior. We monitored females on treatment and control units to determine if food supplementation influenced: 1) nest initiation, nesting duration, and nesting attempts, 2) nesting success, and 3) egg volume and clutch size. We radio‐marked 196 female bobwhites during the breeding season of 2011 and 2012. Hens with access to supplemental feed produced 0.86 and 1.60 nest per hen while hens on control sites produced 0.15 and 0.81 nest per hen during the 2011 and 2012 nesting season, respectively. Average nest initiation varied slightly between treatment and control; though, average nesting season length was 16 and 31 days longer on treatment units. This benefit indicates females with access to food supplementation were in better physical condition compared to females on control units. However, nest success (β = ‐0.03, SE = 0.40), clutch size (t=‐0.37, p = 0.70), and average intra‐clutch egg volumes (β =‐0.06, SE = 0.20) (t=0.50, p= 0.61) were unaffected by food supplementation. Total net productivity estimates showed more chicks per hen were produced on treatment sites [ = 2.34, SE = 0.04 (2011); = 5.75, SE = 0.12 (2012)] than control units [ = 0.61, SE = 0.001 (2011); = 3.47, SE = 0.13 (2012)]. Our results suggest that bobwhites with access to supplemental feed broadcast into roadside vegetation throughout the breeding season can potentially increase nesting attempts which may result in increased production and offset population fluctuations due to drought conditions. [ABSTRACT FROM AUTHOR]

ABSTRACT Declines in northern bobwhite ( Colinus virginianus) populations have led landowners in Texas, USA, to develop various management strategies to combat waning abundance. One common management strategy is to provide supplemental feed to bobwhites, despite the paucity of information regarding the effects of supplemental feed on bobwhite space use and survival. We examined survival and home range of bobwhites using the technique of spreading supplemental feed into roadside vegetation in the Texas Rolling Plains. The study sites were divided into 8 (404.6-ha) units randomly designated as treatment (feed provided) or control (feed withheld). Treatment and control units were rotated during the second field season to minimize potential habitat bias. Treatment units received approximately 69.1 kg/km of milo ( Sorghum bicolor) twice per month. We captured and radiomarked 197 female bobwhites (82 treatment [48: 2010-2011; 34: 2011-2012], 115 control [64: 2010-2011; 51: 2011-2012]) from autumn 2010 to spring 2012. Females were monitored for location and survival with radiotelemetry 3-4 times/week. Average home-range size was similar on control and treatment units (47.6 ha [8.7 SE] and 46.2 ha [10.3 SE], respectively). We estimated survival rate with the nest survival model in Program MARK. We observed an increase in survival rate on treatment units compared with control units, regardless of year or environmental conditions. Our results suggest that distributing supplemental feed into roadside vegetation positively influences bobwhite survival with no reduction in home range size. © 2015 The Wildlife Society. [ABSTRACT FROM AUTHOR]

There is a paucity of information concerning northern bobwhite ( Colinus virginianus) chick demography caused by a deficiency of efficient published capture techniques and permanent unique markers for identification. In order to facilitate chick research, we employed a thermal camera to detect and capture chicks during the preflight stage (≤14 days old) brooded by a radiomarked female. We released a known number of chicks into native vegetation within a flight pen to test this technique. Observers (unaware of the number) then used a thermal camera to successfully count (≥95% intra-class correlation coeff.; complete counts for each age class) and capture the chicks. In separate field tests, we homed to within 10 m of the roost location of wild radiomarked females before sunrise, circled the area until the brood heat signature was observed, and flushed the female from the chicks. We located 116 chicks from 43 broods with the thermal camera throughout the 2011 nesting season with 81% complete, 12% partial, and 7% failed captures attempts. Detection of chicks by the thermal camera was not affected by age. Complete brood abandonment was not detected as a result of capture events. The employment of a thermal camera to capture chicks should advance the success and efficiency of capture and thus promote research concerning brood ecology. © 2012 The Wildlife Society. [ABSTRACT FROM AUTHOR]