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Nestling Tree Swallow (Tachycineta Bicolor) Diets In An Upland Old Field In Western Michigan, Matthew Johnson, Michael Lombardo Jul 2010

Nestling Tree Swallow (Tachycineta Bicolor) Diets In An Upland Old Field In Western Michigan, Matthew Johnson, Michael Lombardo

Michael P Lombardo

We collected and identified 1852 prey items from 89 boluses delivered to 62 nestling tree swallows (Tachycineta bicolor) at 14 nests in an upland old field in western Michigan. We found that 90.8% of nestling diets was insects from the Orders Diptera, Homoptera, Hymenoptera and Coleoptera. We also found clam and snail shells in boluses. Over the most common brood sizes of 4-6 nestlings, brood size was inversely proportional to the number of items per bolus delivered to nestlings although mean dry and mean organic weight of boluses did not differ. Bolus composition was not influenced by weather conditions ...


Effect Of Feathers As Nest Insulation On Incubation Behavior And Reproductive Performance Of Tree Swallows (Tachycineta Bicolor), Michael Lombardo, Ruth Bosman, Christine Faro, Stephen Houtteman, Timothy Kluisza Jul 2010

Effect Of Feathers As Nest Insulation On Incubation Behavior And Reproductive Performance Of Tree Swallows (Tachycineta Bicolor), Michael Lombardo, Ruth Bosman, Christine Faro, Stephen Houtteman, Timothy Kluisza

Michael P Lombardo

Many species of birds line their nests with feathers, presumably because of the insulative qualities of feathers and because feathers may act as a barrier between nest parasites and nestlings. In 1993, we experimentally examined the role of feathers as nest insulation on the incubation behavior, nestling growth, and reproductive performance of Tree Swallows (Tachycineta bicolor) nesting in boxes in western Michigan. There were no significant differences between the incubation rhythms of females with experimental nests (i.e. no feathers) and females with control nests (i.e. with feathers). Nestlings that were reared in control nests had significantly longer right ...


Repeated Sampling Affects Tree Swallow Semen Characteristics, Michael Lombardo, M.L. Green, P.A. Thorpe, M.R. Czarnowski, H.W. Power Jul 2010

Repeated Sampling Affects Tree Swallow Semen Characteristics, Michael Lombardo, M.L. Green, P.A. Thorpe, M.R. Czarnowski, H.W. Power

Michael P Lombardo

Male Tree Swallows (Tachycineta bicolor) face intense sperm competition because mated pairs copulate frequently, extra-pair copulations are common, and females store sperm. We examined the effects of repeated sampling on the characteristics of Tree Swallow semen by manually expressing semen from 15 males immediately after capture (T0) and then hourly for 4 h (T1-T4). The semen characteristics of individual males varied in response to repeated sampling. The total number of sperm cells we obtained from each male over the 4-h sampling period varied from 104-107. Semen samples lacking sperm increased from 6.7 ...


Communities Of Cloacal Bacteria In Tree Swallow Families, Michael Lombardo, Patrick Thorpe, R. Cichewicz, M. Henshaw, C. Millard, C. Steen, T. Zeller Jul 2010

Communities Of Cloacal Bacteria In Tree Swallow Families, Michael Lombardo, Patrick Thorpe, R. Cichewicz, M. Henshaw, C. Millard, C. Steen, T. Zeller

Michael P Lombardo

Our aim in this study was to survey the communities of bacteria found in the cloacae of adult and nestling Tree Swallows (Tachycineta bicolor), determine if there were familial patterns of prevalence, and determine if there were relationships between bacteria loads and nestling size when 12 days old and fledging success.


Left-Sided Directional Bias Of Cloacal Contacts During House Sparrow Copulations, Karen Nyland, Michael Lombardo, Patrick Thorpe Jul 2010

Left-Sided Directional Bias Of Cloacal Contacts During House Sparrow Copulations, Karen Nyland, Michael Lombardo, Patrick Thorpe

Michael P Lombardo

Most female birds have only a left ovary and associated oviduct. The entry to the oviduct is on the left side of the urodeum of the cloaca. This arrangement may favor males that mount females from the left during copulation if it results in sperm being placed closer to the opening of the oviduct. Therefore, we predicted a left-sided directional bias of cloacal contacts during House Sparrow (Passer domesticus) copulations. Cloacal contacts from the left outnumbered those from the right 74 to 25 (3:1) during 25 bouts of copulation at 11 House Sparrow nests. While this pattern suggests that ...


Homosexual Copulations By Male Tree Swallows, Michael P. Lombardo, Ruth M. Bosman, Christine A. Faro, Stephen G. Houtteman, Timothy S. Kluisza Jul 2010

Homosexual Copulations By Male Tree Swallows, Michael P. Lombardo, Ruth M. Bosman, Christine A. Faro, Stephen G. Houtteman, Timothy S. Kluisza

Michael P Lombardo

Homosexual courtship behavior in non-human animals is well known (Ford and Beach 1980) and occurs in a wide variety of taxa. However, homosexual copulations, especially between males, are less well known. In birds, males mounting other males have been observed in the colonially breeding Cattle Egret (Bubulcus ibis) (Fujioka and Yamagishi 1981) and Common Murre (Uria aalge) (Birkhead et al. 1985, Hatchwell 1988). Neither Fujioka and Yamagishi (1981) nor Birkhead et al. (1985) and Hatchwell (1988) reported whether cloacal contact occurred during their observations of male-male mountings. Here we describe homosexual copulations by male Tree Swallows (Tachycineta bicolor) during which ...


Individual, Temporal, And Seasonal Variation In Sperm Concentration In Tree Swallows, Michael Lombardo, Armetris Forman, Matthew Czarnowski, Patrick Thorpe Jul 2010

Individual, Temporal, And Seasonal Variation In Sperm Concentration In Tree Swallows, Michael Lombardo, Armetris Forman, Matthew Czarnowski, Patrick Thorpe

Michael P Lombardo

We determined sperm concentrations in Tree Swallows (Tachycineta bicolor) by manually expressing semen samples from males during prelaying, egg-laying, incubation, and nestling periods. Sperm concentrations varied by orders of magnitude (0-109 sperm mL-1) among males. Sperm concentrations were highest during the incubation period and lowest during the prelaying period. None of the samples collected during the prelaying, egg-laying, and incubation periods were devoid of sperm. In contrast, 45% of samples collected during the nestling period lacked sperm. Sperm concentrations (1) did not vary over the course of the morning during prelaying, egg-laying, and incubation periods but significantly increased during the ...


Microbial Colonization Of The Cloacae Of Nestling Tree Swallows, Tamara Mills, Michael Lombardo, Patrick Thorpe Jul 2010

Microbial Colonization Of The Cloacae Of Nestling Tree Swallows, Tamara Mills, Michael Lombardo, Patrick Thorpe

Michael P Lombardo

Microbes have the potential to be important selective forces in many aspects of avian biology. Microbes can affect fitness as a result of either their pathogenic or beneficial effects on host health. Little is known about the chronology of microbial colonization of nestlings or the effects of microbes on fledgling condition. We set out to (1) characterize the time course of microbial colonization of the cloacae of nestling Tree Swallows (Tachycineta bicolor), (2) examine the relationship between cloacal microbes and fledgling condition, and (3) determine if nest mates had similar assemblages of cloacal microbes. We repeatedly measured nestlings and sampled ...


Within-Pair Copulations: Are Female Tree Swallows Feathering Their Own Nests?, Michael Lombardo Jul 2010

Within-Pair Copulations: Are Female Tree Swallows Feathering Their Own Nests?, Michael Lombardo

Michael P Lombardo

A variety of hypotheses has been proposed to explain why socially monogamous birds copulate repeatedly with their mates when only a single copulation is necessary to fertilize an entire clutch (Birkhead and Møller 1992, Petrie 1992, Hunter et al. 1993). Petrie (1992) hypothesized that a female should copulate frequently with her mate so as to reduce her mate’s involvement in extrapair copulations. By reducing her mate’s involvement in extrapair copulations, a female may: (1) avoid the transmission of parasites and sexually transmitted diseases (Hamilton 1990); (2) may avoid sperm depletion by her mate; and (3) may monopolize her ...


On The Evolution Of Sexually Transmitted Diseases In Birds, Michael Lombardo Jul 2010

On The Evolution Of Sexually Transmitted Diseases In Birds, Michael Lombardo

Michael P Lombardo

"The definitive version is available at www.blackwell-synergy.com".

Sexually transmitted diseases (STDs) in animals are caused by pathogens that are transmitted during copulation. Birds have played an important role in the development of STD-centered theories of mating behavior. However, it is not known whether STDs exist in wild bird populations. While the avian cloaca with its dual functions of gamete transfer and excretion seemingly predisposes birds for the evolution of STDs, the life history patterns of most birds (i.e., seasonal breeders with relatively brief annual periods of sexual activity) suggest otherwise. The importance of STDs as selective forces ...


Left-Sided Directional Bias Of Cloacal Contacts During Tree Swallow Copulations, Aaron Petersen, Michael Lombardo, Harry Power Jul 2010

Left-Sided Directional Bias Of Cloacal Contacts During Tree Swallow Copulations, Aaron Petersen, Michael Lombardo, Harry Power

Michael P Lombardo

Most female birds have only a left ovary and associated oviduct with entry to the oviduct on the left side of the urodeum of the cloaca. We hypothesized that male cloacal contacts during copulation would occur from the left side of females because this would put sperm closer to the entrance of the oviduct. We observed that cloacal contacts from the left outnumbered those from the right by a margin of 3:1 during tree swallow, Tachycineta bicolor, copulations at nestboxes in western Michigan in 1999. The directional bias of cloacal contacts may have an adaptive function.


The Beneficial Sexually Transmitted Microbe Hypothesis Of Avian Copulation, Michael Lombardo, Patrick Thorpe, Harry Power Jul 2010

The Beneficial Sexually Transmitted Microbe Hypothesis Of Avian Copulation, Michael Lombardo, Patrick Thorpe, Harry Power

Michael P Lombardo

Several hypotheses have been proposed to explain why female birds either copulate repeatedly with a single mate or copulate with multiple partners even though only a single copulation may be sufficient to fertilize an entire clutch. We hypothesize that females may directly benefit from high frequencies of copulation and multiple copulation partners if they receive a cloacal inoculation of beneficial sexually transmitted microbes (STMs) that can either protect them against future encounters with pathogens and/or serve as therapy against present infections. Experiments in domestic animal production, wildlife rehabilitation, and clinical medicine indicate that inoculations of beneficial microbes derived from ...


Left-Sided Directional Bias Of Cloacal Contacts During House Sparrow Copulations, Karen B. Nyland, Michael P. Lombardo, Patrick A. Thorpe Dec 2003

Left-Sided Directional Bias Of Cloacal Contacts During House Sparrow Copulations, Karen B. Nyland, Michael P. Lombardo, Patrick A. Thorpe

Peer Reviewed Publications

Most female birds have only a left ovary and associated oviduct. The entry to the oviduct is on the left side of the urodeum of the cloaca. This arrangement may favor males that mount females from the left during copulation if it results in sperm being placed closer to the opening of the oviduct. Therefore, we predicted a left-sided directional bias of cloacal contacts during House Sparrow (Passer domesticus) copulations. Cloacal contacts from the left outnumbered those from the right 74 to 25 (3:1) during 25 bouts of copulation at 11 House Sparrow nests. While this pattern suggests that ...


Individual, Temporal, And Seasonal Variation In Sperm Concentration In Tree Swallows, Michael P. Lombardo, Armetris N. Forman, Matthew R. Czarnowski, Patrick A. Thorpe Nov 2002

Individual, Temporal, And Seasonal Variation In Sperm Concentration In Tree Swallows, Michael P. Lombardo, Armetris N. Forman, Matthew R. Czarnowski, Patrick A. Thorpe

Peer Reviewed Publications

We determined sperm concentrations in Tree Swallows (Tachycineta bicolor) by manually expressing semen samples from males during prelaying, egg-laying, incubation, and nestling periods. Sperm concentrations varied by orders of magnitude (0-109 sperm mL-1) among males. Sperm concentrations were highest during the incubation period and lowest during the prelaying period. None of the samples collected during the prelaying, egg-laying, and incubation periods were devoid of sperm. In contrast, 45% of samples collected during the nestling period lacked sperm. Sperm concentrations (1) did not vary over the course of the morning during prelaying, egg-laying, and incubation periods but significantly increased ...


Nestling Tree Swallow (Tachycineta Bicolor) Diets In An Upland Old Field In Western Michigan, Matthew E. Johnson, Michael P. Lombardo Jul 2000

Nestling Tree Swallow (Tachycineta Bicolor) Diets In An Upland Old Field In Western Michigan, Matthew E. Johnson, Michael P. Lombardo

Peer Reviewed Publications

We collected and identified 1852 prey items from 89 boluses delivered to 62 nestling tree swallows (Tachycineta bicolor) at 14 nests in an upland old field in western Michigan. We found that 90.8% of nestling diets was insects from the Orders Diptera, Homoptera, Hymenoptera and Coleoptera. We also found clam and snail shells in boluses. Over the most common brood sizes of 4-6 nestlings, brood size was inversely proportional to the number of items per bolus delivered to nestlings although mean dry and mean organic weight of boluses did not differ. Bolus composition was not influenced by weather conditions ...


Microbial Colonization Of The Cloacae Of Nestling Tree Swallows, Tamara K. Mills, Michael P. Lombardo, Patrick A. Thorpe Jan 1999

Microbial Colonization Of The Cloacae Of Nestling Tree Swallows, Tamara K. Mills, Michael P. Lombardo, Patrick A. Thorpe

Peer Reviewed Publications

Microbes have the potential to be important selective forces in many aspects of avian biology. Microbes can affect fitness as a result of either their pathogenic or beneficial effects on host health. Little is known about the chronology of microbial colonization of nestlings or the effects of microbes on fledgling condition. We set out to (1) characterize the time course of microbial colonization of the cloacae of nestling Tree Swallows (Tachycineta bicolor), (2) examine the relationship between cloacal microbes and fledgling condition, and (3) determine if nest mates had similar assemblages of cloacal microbes. We repeatedly measured nestlings and sampled ...


Communities Of Cloacal Bacteria In Tree Swallow Families, Michael P. Lombardo, Patrick A. Thorpe, R. Cichewicz, M. Henshaw, C. Millard, C. Steen, T. K. Zeller Jan 1996

Communities Of Cloacal Bacteria In Tree Swallow Families, Michael P. Lombardo, Patrick A. Thorpe, R. Cichewicz, M. Henshaw, C. Millard, C. Steen, T. K. Zeller

Peer Reviewed Publications

Our aim in this study was to survey the communities of bacteria found in the cloacae of adult and nestling Tree Swallows (Tachycineta bicolor), determine if there were familial patterns of prevalence, and determine if there were relationships between bacteria loads and nestling size when 12 days old and fledging success.


Effect Of Feathers As Nest Insulation On Incubation Behavior And Reproductive Performance Of Tree Swallows (Tachycineta Bicolor), Michael P. Lombardo, Ruth M. Bosman, Christine A. Faro, Stephen G. Houtteman, Timothy S. Kluisza Jan 1995

Effect Of Feathers As Nest Insulation On Incubation Behavior And Reproductive Performance Of Tree Swallows (Tachycineta Bicolor), Michael P. Lombardo, Ruth M. Bosman, Christine A. Faro, Stephen G. Houtteman, Timothy S. Kluisza

Peer Reviewed Publications

Many species of birds line their nests with feathers, presumably because of the insulative qualities of feathers and because feathers may act as a barrier between nest parasites and nestlings. In 1993, we experimentally examined the role of feathers as nest insulation on the incubation behavior, nestling growth, and reproductive performance of Tree Swallows (Tachycineta bicolor) nesting in boxes in western Michigan. There were no significant differences between the incubation rhythms of females with experimental nests (i.e. no feathers) and females with control nests (i.e. with feathers). Nestlings that were reared in control nests had significantly longer right ...


Within-Pair Copulations: Are Female Tree Swallows Feathering Their Own Nests?, Michael P. Lombardo Jan 1995

Within-Pair Copulations: Are Female Tree Swallows Feathering Their Own Nests?, Michael P. Lombardo

Peer Reviewed Publications

A variety of hypotheses has been proposed to explain why socially monogamous birds copulate repeatedly with their mates when only a single copulation is necessary to fertilize an entire clutch (Birkhead and Møller 1992, Petrie 1992, Hunter et al. 1993). Petrie (1992) hypothesized that a female should copulate frequently with her mate so as to reduce her mate’s involvement in extrapair copulations. By reducing her mate’s involvement in extrapair copulations, a female may: (1) avoid the transmission of parasites and sexually transmitted diseases (Hamilton 1990); (2) may avoid sperm depletion by her mate; and (3) may monopolize her ...


Homosexual Copulations By Male Tree Swallows, Michael P. Lombardo, Ruth M. Bosman, Christine A. Faro, Stephen G. Houtteman, Timothy S. Kluisza Jan 1994

Homosexual Copulations By Male Tree Swallows, Michael P. Lombardo, Ruth M. Bosman, Christine A. Faro, Stephen G. Houtteman, Timothy S. Kluisza

Peer Reviewed Publications

Homosexual courtship behavior in non-human animals is well known (Ford and Beach 1980) and occurs in a wide variety of taxa. However, homosexual copulations, especially between males, are less well known. In birds, males mounting other males have been observed in the colonially breeding Cattle Egret (Bubulcus ibis) (Fujioka and Yamagishi 1981) and Common Murre (Uria aalge) (Birkhead et al. 1985, Hatchwell 1988). Neither Fujioka and Yamagishi (1981) nor Birkhead et al. (1985) and Hatchwell (1988) reported whether cloacal contact occurred during their observations of male-male mountings. Here we describe homosexual copulations by male Tree Swallows (Tachycineta bicolor) during which ...


Behavioral Feeding Specialization In Pinaroloxias Inornata, The “Darwin's Finch” Of Cocos Island, Costa Rica, Tracey K. Werner, Thomas W. Sherry Apr 1987

Behavioral Feeding Specialization In Pinaroloxias Inornata, The “Darwin's Finch” Of Cocos Island, Costa Rica, Tracey K. Werner, Thomas W. Sherry

Open Dartmouth: Faculty Open Access Articles

As a population, Cocos Finches exhibit a broad range of feeding behaviors spanning those of several families of birds on the mainland, while individuals feed as specialists year-round. Although this extreme intraspecific variability occurs as predicted in a tropical oceanic island environment, these specializations challenge contemporary ecological theory in that they are not attributable to individual differences in age, sex, gross morphology, or opportunistic exploitation of patchy resources. Instead, they appear to originate and be maintained behaviorally, possibly via observational learning. This phenomenon adds another direction to the evolutionary radiation of the Darwin's Finches and underscores the necessity for ...