Ectoparasites, nestling growth, parental feeding rates, and begging intensity of tree swallows

Many studies fail to show relationships between ectoparasite loads and nestling growth rates. One explanation is that parent birds increase feeding rates to compensate for nestling energetic losses to ectoparasites. Nestling begging behaviours could signal need to parents. Accordingly, we tested whether higher flea and blow fly loads in tree swallow (Tachycineta bicolor) nests were associated with smaller nestlings, higher parental feeding rates, and increased nestling begging intensity. The study area was the Gaspereau Valley of Nova Scotia, Canada. When nestlings were 10 days old, parental feeding rates and nestling begging intensity were measured with tape recorders. At 13 days of age, nestlings were weighed and measured. Within 2 days of fledging, nest material was removed from nest boxes and enumerated for adult fleas and blow fly pupae. After including brood size and date of first egg as covariates in general linear models, no significant relationships were found between ectoparasite loads and nestling size, parental feeding rate, or nestling begging intensity. Our results suggest that nestling tree swallows were able to buffer the effects of naturally occurring ectoparasite loads without significant help from their parents. Low levels of virulence may have resulted from relatively benign weather during the study, low numbers of ectoparasites, selection on ectoparasites to avoid killing their hosts, and host defences.

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Aggression, superterritories, and reproductive success in tree swallows

Canadian Journal of Zoology ◽

10.1139/z79-273 ◽

1979 ◽

Vol 57 (10) ◽

pp. 2072-2078 ◽

Cited By ~ 15

Author(s):

Reid N. Harris

Keyword(s):

Reproductive Success ◽

Reproductive Output ◽

Future Generations ◽

Tree Swallows ◽

Nestling Growth ◽

Territorial Aggression ◽

Nest Boxes ◽

Nestling Period ◽

The Relationship ◽

Insular Population

The relationship between territorial aggression and reproductive success was studied on a well-established, insular population of tree swallows. Four treatments of nest boxes that differed in interbox distances were created. Short interbox distances significantly reduced the occupancy of nest boxes both between and within years. Swallows in short interbox distance treatments defended more than one nest box, which was an additional resource not necessary for their successful reproduction. Excluded potential breeders attempted to colonize vacant boxes within another swallow's territory throughout the nestling period, but were usually prevented by the aggression of the resident pair. Aggressive activity had no direct effect on three measures of a swallow's reproductive output: percent young fledged, nestling growth, and fledgling weights. The concept of intraspecific aggressive neglect is questioned. However, by excluding potential breeders from nesting, for whatever reason, breeding tree swallows increased their relative genetic contribution to future generations.

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The Effects of Parent and Offspring Gender On Food Allocation in Budgerigars

Behaviour ◽

10.1163/156853987x00422 ◽

1987 ◽

Vol 101 (1-3) ◽

pp. 177-199 ◽

Cited By ~ 51

Author(s):

Judy Stamps ◽

Anne Clark ◽

Barbara Kus ◽

Pat Arrowood

Keyword(s):

Reproductive Success ◽

Sex Ratios ◽

Negative Relationship ◽

Female Parent ◽

Feeding Rates ◽

Significant Relationships ◽

Parental Feeding ◽

Highly Correlated ◽

Offspring Gender ◽

Negative Relationships

AbstractParental feeding rates in relation to the sex of parents and offspring were studied in domesticated budgerigars in large flight cages at Davis, California. While neither the male nor the female parent preferentially fed offspring of either sex, paternal feeding rates were strongly related to the sex ratio of the brood. Fathers fed female-biased broods much more frequently than male-biased broods throughout the nest cycle, and male feeding rates were highly correlated with the sex ratios of the broods. Mothers exhibited a similar but much weaker tendency to feed female-biased broods more often, and only at the end of the nest cycle was there a barely significant relationship between sex bias and maternal feeding rate. As a result of the extra parental care, female-biased broods obtained nearly three times more regurgitations in the final pre-fledge period than male-biased broods. Brood sex ratios were unrelated to fledge weights, and male and female nestlings fledged at comparable weights. However, for all but the smallest broods, there was a strong negative relationship between the percent of females within the brood and the average age of fledging. Fledge age, in turn, was related to post-fledge activity rates. Females fledging at younger ages initiated more flights than those fledging at older ages. Conversely, in males, fledge age was either unrelated, or positively related to the rate of flights. There were also significant negative relationships between female fledge age and reproductive success (e.g. number of young fledged in the first breeding season), but no significant relationships between male fledge age and reproductive success. Hence, male parents may provide extra care to broods biased toward the offspring sex which most benefits from this extra care.

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Short-term exposure to unmanned aerial vehicles does not alter stress responses in breeding tree swallows

Conservation Physiology ◽

10.1093/conphys/coaa080 ◽

2020 ◽

Vol 8 (1) ◽

Author(s):

Bradley D Scholten ◽

Abigail R Beard ◽

Hyeryeong Choi ◽

Dena M Baker ◽

Margaret E Caulfield ◽

...

Keyword(s):

Stress Responses ◽

New Technologies ◽

Physiological Stress ◽

Control Object ◽

Tree Swallow ◽

Tree Swallows ◽

Avian Behavior ◽

Nest Boxes ◽

Short Term Exposure ◽

First Results

Abstract Recent studies suggest that visual and acoustic anthropogenic disturbances can cause physiological stress in animals. Human-induced stress may be particularly problematic for birds as new technologies, such as drones, increasingly invade their low-altitude air space. Although professional and recreational drone usage is increasing rapidly, there is little information on how drones affect avian behavior and physiology. We examined the effects of drone activity on behavior and physiology in adult, box-nesting tree swallows (Tachycineta bicolor). Specifically, we monitored bird behavior during drone flights and in response to a control object and measured telomere lengths and corticosterone levels as indicators of longer-term physiological stress. We predicted that drone-exposed tree swallows would habituate behaviorally after multiple flights, but that telomeres would shorten more quickly and that baseline corticosterone levels would be altered. One significant and two strong, non-significant trends in behavioral assays indicated that adult swallows acted more aggressively towards drone presence compared to a control object, but were slower to approach the drone initially. Swallows were also more reluctant to use nest boxes during drone activity. Tree swallows habituated to drone presence as expected, although the rate of habituation often did not differ between drone-exposed and control groups. Contrary to our prediction, drone activity did not affect telomere length, corticosterone levels, body mass or fledging rates. Overall, our results indicate that a small number of short, targeted, drone flights do not impact tree swallow health or productivity differently than a non-invasive control object. Minor behavioral differences suggest that increasing the frequency of drone use could impact this species. We provide some of the first results addressing how drone activity alters behavioral, physiological and molecular responses to stress in songbirds. A better understanding of these impacts will allow ecologists to make more informed decisions on the use and regulation of new drone technologies.

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Size, condition, and territory ownership in male tree swallows (Tachycineta bicolor)

Canadian Journal of Zoology ◽

10.1139/z94-046 ◽

1994 ◽

Vol 72 (2) ◽

pp. 330-333 ◽

Cited By ~ 25

Author(s):

George A. Lozano

Keyword(s):

Dry Mass ◽

Nutritional Condition ◽

Tachycineta Bicolor ◽

Tree Swallow ◽

Tree Swallows ◽

Resource Holding Potential ◽

Nest Boxes ◽

Male Tree ◽

Breeding Grounds ◽

Size Condition

Male tree swallow (Tachycineta bicolor) territory owners and floaters were compared in terms of size and nutritional condition to test the resource holding potential hypothesis. Owners were larger than floaters when compared using six morphological measurements. There were no differences in dry mass, ash, or fat content, but territory owners were heavier and had larger protein reserves than floaters. Territory owners may be those individuals who win intrasexual conflicts for the possession of nest boxes, or those who, because of their better nutritional condition, can arrive at the breeding grounds earlier to secure a territory.

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A comparison of the breeding ecology of a secondary cavity nesting bird, the Tree Swallow (Tachycineta bicolor), in nest boxes and natural cavities

Canadian Journal of Zoology ◽

10.1139/z90-152 ◽

1990 ◽

Vol 68 (5) ◽

pp. 1046-1052 ◽

Cited By ~ 88

Author(s):

Raleigh J. Robertson ◽

Wallace B. Rendell

Keyword(s):

Interspecific Competition ◽

Nest Site ◽

Natural Populations ◽

Tree Swallow ◽

Life History Strategies ◽

Tree Swallows ◽

Nest Box ◽

Nest Boxes ◽

Cavity Nesting ◽

Second Year

Several studies concerned with mate choice, reproductive performance, and life history strategies have been conducted with secondary cavity nesting birds breeding in nest boxes. Although the need for comparative studies has been recognized, populations breeding in nest boxes often have not been compared with those breeding in natural cavities. We compared the ecology of Tree Swallows breeding in nest boxes and natural cavities to determine if nest box populations of Tree Swallows are accurate models of natural populations. Two nest site characteristics, nest site dispersion and cavity height, were similar for birds in both nesting environments. Greater cavity entrance area at natural cavities resulted in increased interspecific competition in natural populations, involving larger competitors, more species, and a greater abundance of each species. Clutch size was smaller in natural cavities compared with nest boxes, likely because floor area was smaller in natural cavities. Fledging success did not differ between populations. Disproportionately more after-second-year females bred in nest boxes, and more second-year females bred in natural cavities, as estimated by a model of Tree Swallow survivorship. Tree Swallows settle at nest boxes before natural cavities in our study area, perhaps as a result of the greater potential for reproductive success and reduced interspecific competition in the nest boxes as opposed to natural cavities. For some aspects of the ecology of secondary cavity nesters, nest boxes do not provide an accurate representation of natural populations. Therefore, evolutionary interpretations of nest box studies should be compared with observations of birds in natural environments.

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Begging calls and parental feeding decisions in tree swallows ( Tachycineta bicolor )

Behavioral Ecology and Sociobiology ◽

10.1007/s002650000290 ◽

2001 ◽

Vol 49 (2-3) ◽

pp. 170-175 ◽

Cited By ~ 75

Author(s):

M. L. Leonard ◽

Andrew G. Horn

Keyword(s):

Tachycineta Bicolor ◽

Tree Swallows ◽

Parental Feeding

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Male parental investment reflects the level of partner contributions and brood value in tree swallows

10.1101/216119 ◽

2017 ◽

Author(s):

Ádám Z. Lendvai ◽

Çağlar Akçay ◽

Mark Stanback ◽

Mark F. Haussmann ◽

Ignacio T. Moore ◽

...

Keyword(s):

Parental Care ◽

Interesting Case ◽

Temporary Increase ◽

Southern Population ◽

Tree Swallows ◽

Parental Effort ◽

Northern Population ◽

Nestling Begging ◽

Two Populations ◽

Partial Compensation

AbstractBiparental care presents an interesting case of cooperation and conflict between unrelated individuals. Several models have been proposed to explain how parents should respond to changes in each other’s parental care to maximize their own fitness, predicting no change, partial compensation, or matching effort as a response. Here, we present an experiment in tree swallows (Tachycineta bicolor) in which we increased the parental care of females by presenting them, but not their mates, with additional nestling begging calls using automated playbacks. We performed this experiment in two populations differing in future breeding opportunities and thus the intensity of conflict over current parental care. We found that in response to a temporary increase in female parental effort, males in the northern population with lower sexual conflict matched the increased effort, whereas males in the southern population did not. We also found that increases in parental care during playbacks were driven by the females (i.e., females initiated the increased effort and their mates followed them) in the northern population but not the southern population. These results support the idea that with incomplete information about the brood value and need, cues or signals from the partner might become important in coordinating parental care.

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Rainfall and nest site competition delay Mountain Bluebird and Tree Swallow breeding but do not impact productivity

The Auk ◽

10.1093/auk/ukaa006 ◽

2020 ◽

Vol 137 (2) ◽

Cited By ~ 1

Author(s):

Anna Drake ◽

Kathy Martin

Keyword(s):

Daily Rainfall ◽

Tree Swallow ◽

Tree Swallows ◽

Breeding Phenology ◽

Productivity Cost ◽

Breeding Sites ◽

Tree Cavities ◽

Mountain Bluebird ◽

Mountain Bluebirds ◽

Study Sites

Abstract Optimizing breeding phenology, an important aspect of fitness, is complex for migratory species as they must make key timing decisions early, and remotely, from breeding sites. We examined the role of weather (locally and cross-seasonally), cavity availability, and competitive exclusion in determining among-year variation in breeding phenology over 17 yr for 2 migratory, cavity-nesting birds: Mountain Bluebirds (Sialia currucoides; n = 462 nests) and Tree Swallows (Tachycineta bicolor; n = 572) using natural tree cavities in British Columbia, Canada. We assessed weather effects within the winter and migratory range and at our study sites. We quantified competition as the proportion of cavities occupied by European Starlings (Sturnus vulgaris) (for both species) and Mountain Bluebirds (for Tree Swallow only) in each year. For 229 bluebird and 177 swallow nests with known fates, we tested whether late years resulted in reduced productivity. Although the effects were small, heavy rainfall and strong diurnal westerly winds during migration were associated with breeding delays for Mountain Bluebirds. However, cavity availability (earlier breeding with increases) had a 5–8 × greater effect on timing than migratory conditions. There was no evidence that starling competition delayed bluebirds. In Tree Swallows, greater local daily rainfall was associated with delayed breeding, as was starling abundance (the effect of starlings was 1.4 × smaller than that of rainfall). Neither bluebird abundance nor cavity availability changed swallow phenology. Neither species showed reduced productivity in late breeding years. In both species, individuals that bred late relative to conspecifics within-year had smaller clutches and greater probability of nest failure. We conclude that breeding ground conditions, particularly cavity limitation and local rainfall (for swallows), are important drivers of breeding phenology for our focal species, but that the productivity cost of late years, at least for Tree Swallows, is minimal.

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Diet of the Nestling Tree Swallow

The Condor ◽

10.1093/condor/106.2.423 ◽

2004 ◽

Vol 106 (2) ◽

pp. 423-429 ◽

Cited By ~ 4

Author(s):

Jean M. Mengelkoch ◽

Gerald J. Niemi ◽

Ronald R. Regal

Keyword(s):

Open Water ◽

Time Of Day ◽

Tachycineta Bicolor ◽

Tree Swallow ◽

Tree Swallows ◽

Larval Stages ◽

Terrestrial Origin ◽

The Mean ◽

Foraging Radius

Abstract Dietary samples from nestling Tree Swallows (Tachycineta bicolor) in northwestern Minnesota were compared to invertebrate availability as measured by aerial tow nets. The majority of the biomass in the nestlings' diet was adult insects with larval stages of aquatic origin, while absolute numbers of insects of both aquatic and terrestrial origin were similar. Orders of invertebrates in the diet and available were similar in number but not in biomass. Diet showed little variation by time of day, date of sampling or the age of the nestling. The mean number of odonates in the nestling Tree Swallows' diet increased exponentially as the percentage of open water and open water + cattail marsh increased within a 400-m foraging radius. Dieta de los Pichones de Tachycineta bicolor Resumen. Se compararon muestras dietarias de pichones de la golondrina Tachycineta bicolor tomadas en el noroeste de Minnesota con la disponibilidad de invertebrados medida con redes aéreas. La mayor parte de la biomasa en la dieta de los pichones correspondió a insectos adultos con estadíos larvales de origen acuá tico, mientras que los números absolutos de insectos de origen acuático y no acuático fueron similares. Los órdenes de invertebrados presentes en la dieta y disponibles en el ambiente fueron similares en números pero no en biomasa. La dieta mostró poca variación entre horas del día, fechas de muestreo o edad de los pichones. El número promedio de odonatos en la dieta de los pichones de T. bicolor aumentó exponencialmente a medida que se incrementó el porcentaje de agua abierta y de agua abierta + pantanos de espadañas dentro de un radio de forrajeo de 400 m.

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