The Peruvian coxtd pumo islands and headlands have been mong the world's best and worst mana... more The Peruvian coxtd pumo islands and headlands have been mong the world's best and worst managed of seabird nesting area?. The islands contained enormous dcoosm of seabird excreta or aumo which wm minrdforfrrtilizcrin thenineteenthcentury In theearly twen~ tmh century, with euano dcpasits exhausted and bird populations dmost exterminated by the exploiters, the Peruvian government nationalized the islmds and began to manage them ma sustvinablc resource. protecting the birds, imprwing their nesting i; ites. and taking only! he ...
GOLDSTEIN, M.I., DUFFY, D.C., OEHLERS, S., CATTERSON, N., FREDERICK, J. & PYARE, S. 2019. Interse... more GOLDSTEIN, M.I., DUFFY, D.C., OEHLERS, S., CATTERSON, N., FREDERICK, J. & PYARE, S. 2019. Interseasonal movements and non-breeding locations of Aleutian Terns Onychoprion aleuticus. Marine Ornithology 47: 67–76. Few observations have been made of Aleutian Terns Onychoprion aleuticus outside of summer breeding colonies. We investigateed the nonbreeding distribution of Aleutian Terns by collating published and unpublished records of observations during the migration and wintering periods, and by implementing a geolocator tracking study at the largest known breeding colony in North America (Yakutat, Alaska). We deployed 114 geolocator tags in 2010 and recovered six tags over the course of six years. Using light level data, we conducted spatial analysis of tern migration cycles from 2010 to 2013. Results revealed one of the longest distance terrestrial vertebrate migrations ever recorded, with a one-way migration distance of > 16 000 km between Alaska and the Southeast Asia/Oceania r...
Although the populations and ecologies of seabirds of the world’s larger upwelling ecosystems are... more Although the populations and ecologies of seabirds of the world’s larger upwelling ecosystems are relatively well studied (e.g. Murphy 1936, Duffy et al. 1987, Spear & Ainley 2008, Ainley & Hyrenbach 2009), comparatively little is known of the seabirds of many smaller upwelling ecosystems. This paper reports on inshore seabird distributions and numbers around the Santa Elena Peninsula in the Gulf of Papagayo, off northwestern Costa Rica, in relation to surface water temperature. We also present general observations on island breeding and roosting sites, as well as initial data on foraging.
How species come to be established on islands and their consequent adaptations and evolution are ... more How species come to be established on islands and their consequent adaptations and evolution are subjects that lie at the heart of much of ecology and evolutionary and conservation biology. On islands, small populations, limited gene diversity and flow, and simpler ecosystems facilitate our understanding of how species arrive and then adapt and evolve in new locations. One component of this is understanding how the transition from arrival to establishment may affect species and their parasites and diseases. Colonizing species may arrive without the full burdens of parasites weighing on their source populations, allowing them to reduce their energetic investments in immune defenses. However, reduced genetic diversity may also reduce populations through inbreeding depression or diminish capacity to evolve. Loss of genes and adaptation to novel environments may over time reduce the capacity of insular species to deal with new parasites or old ones that “catch up.” With increasing anthr...
Señor William Vogt, a la terminación del contracto de tres años que con autorización del Supremo ... more Señor William Vogt, a la terminación del contracto de tres años que con autorización del Supremo Gobierno celebrara con la Compañia, con el fin de que llevara a cabo estudios relativos a la mejor forma de protección de las aves guaneras y aumento de la produción de las aves guaneras. Boletín de la
Marine Ornithology 43: 133–134 (2015) Kleptoparasitism, or food piracy, is widespread among seabi... more Marine Ornithology 43: 133–134 (2015) Kleptoparasitism, or food piracy, is widespread among seabirds (Brockmann & Barnard 1979, Furness 1987), leading seabirds to adopt various strategies to avoid being parasitized. These include choice of nesting location (Nettleship 1972), changes in flight altitude and behavior when approaching the colony or nest site (Grant 1971), diving underwater to escape aerial pursuit (Grant 1971), avoiding situations in which the ratio of parasites is large relative to potential victims (Grant 1971, Blackburn et al. 2009) and decreasing the same ratio by defensively aggregating as flocks, as do other organisms (e.g. Hamilton 1971, Falconer 1976, Courchamp et al. 2002, Carbone et al. 2005). This note reports on the apparent use of the last strategy by Brown Boobies Sula leucogaster to avoid parasitism by Magnificent Frigatebirds Fregata magnificens. BROWN BOOBY SULA LEUCOGASTER GROUP SIZE AS A DEFENSE AGAINST KLEPTOPARASITISM
Millions of birds in the United States die annually due to vehicle collisions on roads. Collision... more Millions of birds in the United States die annually due to vehicle collisions on roads. Collisions may be of particular interest for species of conservation concern, such as the endangered Hawaiian goose (Nē nē), which is endemic to Hawai'i. Using a nearly 40-year dataset of Nē nē road mortality in and around Hawai'i Volcanoes National Park, we sought to answer the following research questions: 1) has Nē nē mortality changed over time? 2) are there times of the year in which mortality is greatest and does it relate to specific events in the species' lifecycle? 3) does age at mortality differ over time, space, or sex? 4) given that existing mortalities appear to occur only in certain locations, do the number of mortality events differ across these locations; 5) does mortality rate show any density dependence? and, 6) are mortality rates related to numbers of visitors or vehicles? Between 1977 and 2014, a total of 92 Nē nē died from vehicle collisions; while absolute mortality increased over this time, the mortality rate remained the same. Similarly, average age of mortality increased over time, but did not differ by location or sex. Between 1995 and 2014, Nē nē population size and mortality rates were not correlated. Mortality was greatest in November and December (breeding season) and lowest in June. Most of the mortality occurred along just three stretches of road in and around the park, with the number of mortalities split about evenly inside and outside of the park. Furthermore, Nē nē mortality was unrelated to the number of visitors or traffic volume in the park. These findings suggest vehicle collisions are a growing concern for Nē nē , but that management actions to reduce mortality can be targeted at specific road segments and times of the year.
Evolution in the Hawaiian Islands has produced a unique avian assemblage. Unfortunately, many of ... more Evolution in the Hawaiian Islands has produced a unique avian assemblage. Unfortunately, many of these bird species are highly endangered or extinct. Despite numerous and increasing threats and great effort aimed at saving endemic birds, we lack basic science necessary for understanding many species of concern. One such species is the critically endangered Puaiohi (Myadestes palmeri), a rare songbird endemic to the island of Kaua'i and the only remaining native thrush on the island. At present, the Puaiohi's breeding population is estimated to be ~500 birds restricted to the Alaka'i Wilderness Preserve. We collected demographic data from 2007-2012 and supplemented it with published sources. Using Vortex, we developed stochastic population models to represent Puaiohi population dynamics under current and potential management scenarios to determine management's potential efficacy in aiding species recovery. Management scenarios modeled included rat control, habitat imp...
The island of Kaua'i, Hawai'i has several remaining populations of endangered, endemic Hawaiian p... more The island of Kaua'i, Hawai'i has several remaining populations of endangered, endemic Hawaiian petrels (Pteradroma sandwichensis) and Newell's shearwaters (Pr�fji.nus newelli) that would be threatened by the presence of pred atory mongooses (Herpestes javrmicus). Despite over 200 putative sightings, 1 road-kill and 2 recent captures, it is not clear if mongooses actually be come established on Kaua'i. Comparing road transects on three Hawaiian is lands, we found mongooses present on O'ahu and Maui where they are known to occur and no evidence of significant populations on Kaua'i. Three popula tion scenarios are presented that would account for the three specimens, the past sightings, and the absence of sightings on our transects on Kaua'i.
The miconia (Miconia calvescens) invasion of the East Maui Watershed (EMW) started from a single ... more The miconia (Miconia calvescens) invasion of the East Maui Watershed (EMW) started from a single introduction over 40 yr ago, establishing a nascent patch network spread across 20,000 ha. In 2012, an accelerated intervention strategy was implemented utilizing the Herbicide Ballistic Technology (HBT) platform in a Hughes 500D helicopter to reduce target densities of seven nascent patches in the EMW. In a 14-mo period, a total of 48 interventions eliminated 4,029 miconia targets, with an estimated 33% increase in operations and 168% increase in recorded targets relative to the adjusted means from 2005 to 2011 data (prior to HBT adoption). This sequence of interventions covered a total net area of 1,138 ha, creating a field mosaic of overlapping search coverage (saturation) for each patch (four to eight interventions per patch). Target density reduction for each patch fit exponential decay functions (R 2 > 0.88, P < 0.05), with a majority of the target interventions spatially ass...
Nymphal Irodes sconularis Say deer ticks wcre collected at 22 narks or other natural areas on ~on... more Nymphal Irodes sconularis Say deer ticks wcre collected at 22 narks or other natural areas on ~ong Island, Nc& York, to examine the relationship betwe& tick popu- lations and geographic position, size of area, grescnce of white-tailed deer, Odocoileus virginionus (Limmerman), and numbcrs of human Lymr disease cases in acljliacent com- munities. Nymphal ticks were 93% less abundant when dew were ahsent and were also less common iu smaller natural arcas. Geographic position on Long Island was not impor- tant. Tick numbers were significantly correlated with human Lyme discasc incidence in adjacent townships. A second survey oflarval ticks from fivc areas whcm deer werc absent and six where deer were present found larvae present at four of the five sites without deer, but at only 2% of the levels found where deer were present. These results suggest that populations of I. scapularis can occur and reproduce in the absence of white-tailed decr, so that eradication of all deer would greatly...
Health on whether any sanctions should be imposed by DHHS and, if so, what they should be. As the... more Health on whether any sanctions should be imposed by DHHS and, if so, what they should be. As the biomedical and behavioral research community continues to adopt policies and procedures that deal effectively with allegations or suspicions of scientific misconduct, the OSI should find fewer occasions to conduct its own investigations. Strong institutional frameworks for dealing with scientific misconduct also will enable the PHS to focus on its primary responsibilities in this area; namely, monitoring institutional compliance with PHS policies and regulations and developing prevention and education programs. It is widely believed that scientific misconduct is not widespread. Nevertheless, even a small number of instances of scientific misconduct is unacceptable. As the steward of the vast majority of available federal awards for biomedical and behavioral research, the PHS will ensure that an effective process is in place for dealing with scientific misconduct.
The introduction of mammalian predators onto islands with terrestrially breeding seabirds can res... more The introduction of mammalian predators onto islands with terrestrially breeding seabirds can result in profoundly negative effects for breeding success and eventually for populations of the birds (e.g. Moors & Atkinson 1984). The preferred response is to remove such predators, and there are numerous successful examples (Towns et al. 1997, Nogales et al. 2004, Parkes et al. 2014). However, if complete predator removal is logistically impossible and complicated by the presence of multiple introduced predators, effective management may become more problematic. In such instances, knowledge of the relative damage contributed by each predator species may be helpful, so that limited resources can be directed at the species and management efforts that would be likely to have the greatest positive effect on seabirds and other native fauna.
Marine bird populations interact with fisheries in a variety of ways, with diverse outcomes. Eval... more Marine bird populations interact with fisheries in a variety of ways, with diverse outcomes. Evaluation of these outcomes requires a means of comparison across cases, and a means of identifying the relative importance of concomitant processes at relevant space and time scales. We describe a general quantitative framework that permits comparison of quantitative findings among studies of seabird-fisheries interactions. We then review the results of seabird-fsheries studies within this framework. We discuss the use of ad hoc ratios and dimensional analysis to make decisions about competing processes at relevant space and time scales.
When searching for prey, animals should maximize energetic gain, while minimizing energy expendit... more When searching for prey, animals should maximize energetic gain, while minimizing energy expenditure by altering their movements relative to prey availability. However, with increasing amounts of marine debris, what once may have been 'optimal' foraging strategies for top marine predators, are leading to sub-optimal diets comprised in large part of plastic. Indeed, the highly vagile Laysan albatross (Phoebastria immutabilis) which forages throughout the North Pacific, are well known for their tendency to ingest plastic. Here we examine whether Laysan albatrosses nesting on Kure Atoll and Oahu Island, 2,150 km apart, experience different levels of plastic ingestion. Twenty two geolocators were deployed on breeding adults for up to two years. Regurgitated boluses of undigestable material were also collected from chicks at each site to compare the amount of plastic vs. natural foods. Chicks from Kure Atoll were fed almost ten times the amount of plastic compared to chicks from Oahu despite boluses from both colonies having similar amounts of natural food. Tracking data indicated that adults from either colony did not have core overlapping distributions during the early half of the breeding period and that adults from Kure had a greater overlap with the putative range of the Western Garbage Patch corroborating our observation of higher plastic loads at this colony. At-sea distributions also varied throughout the year suggesting that Laysan albatrosses either adjusted their foraging behavior according to constraints on time away from the nest or to variation in resources. However, in the non-breeding season, distributional overlap was greater indicating that the energy required to reach the foraging grounds was less important than the total energy available. These results demonstrate how a marine predator that is not dispersal limited alters its foraging strategy throughout the reproductive cycle to maximize energetic gain and how this has led to differences in plastic ingestion. Citation: Young LC, Vanderlip C, Duffy DC, Afanasyev V, Shaffer SA (2009) Bringing Home the Trash: Do Colony-Based Differences in Foraging Distribution Lead to Increased Plastic Ingestion in Laysan Albatrosses? PLoS ONE 4(10): e7623.
The Peruvian coxtd pumo islands and headlands have been mong the world's best and worst mana... more The Peruvian coxtd pumo islands and headlands have been mong the world's best and worst managed of seabird nesting area?. The islands contained enormous dcoosm of seabird excreta or aumo which wm minrdforfrrtilizcrin thenineteenthcentury In theearly twen~ tmh century, with euano dcpasits exhausted and bird populations dmost exterminated by the exploiters, the Peruvian government nationalized the islmds and began to manage them ma sustvinablc resource. protecting the birds, imprwing their nesting i; ites. and taking only! he ...
GOLDSTEIN, M.I., DUFFY, D.C., OEHLERS, S., CATTERSON, N., FREDERICK, J. & PYARE, S. 2019. Interse... more GOLDSTEIN, M.I., DUFFY, D.C., OEHLERS, S., CATTERSON, N., FREDERICK, J. & PYARE, S. 2019. Interseasonal movements and non-breeding locations of Aleutian Terns Onychoprion aleuticus. Marine Ornithology 47: 67–76. Few observations have been made of Aleutian Terns Onychoprion aleuticus outside of summer breeding colonies. We investigateed the nonbreeding distribution of Aleutian Terns by collating published and unpublished records of observations during the migration and wintering periods, and by implementing a geolocator tracking study at the largest known breeding colony in North America (Yakutat, Alaska). We deployed 114 geolocator tags in 2010 and recovered six tags over the course of six years. Using light level data, we conducted spatial analysis of tern migration cycles from 2010 to 2013. Results revealed one of the longest distance terrestrial vertebrate migrations ever recorded, with a one-way migration distance of > 16 000 km between Alaska and the Southeast Asia/Oceania r...
Although the populations and ecologies of seabirds of the world’s larger upwelling ecosystems are... more Although the populations and ecologies of seabirds of the world’s larger upwelling ecosystems are relatively well studied (e.g. Murphy 1936, Duffy et al. 1987, Spear & Ainley 2008, Ainley & Hyrenbach 2009), comparatively little is known of the seabirds of many smaller upwelling ecosystems. This paper reports on inshore seabird distributions and numbers around the Santa Elena Peninsula in the Gulf of Papagayo, off northwestern Costa Rica, in relation to surface water temperature. We also present general observations on island breeding and roosting sites, as well as initial data on foraging.
How species come to be established on islands and their consequent adaptations and evolution are ... more How species come to be established on islands and their consequent adaptations and evolution are subjects that lie at the heart of much of ecology and evolutionary and conservation biology. On islands, small populations, limited gene diversity and flow, and simpler ecosystems facilitate our understanding of how species arrive and then adapt and evolve in new locations. One component of this is understanding how the transition from arrival to establishment may affect species and their parasites and diseases. Colonizing species may arrive without the full burdens of parasites weighing on their source populations, allowing them to reduce their energetic investments in immune defenses. However, reduced genetic diversity may also reduce populations through inbreeding depression or diminish capacity to evolve. Loss of genes and adaptation to novel environments may over time reduce the capacity of insular species to deal with new parasites or old ones that “catch up.” With increasing anthr...
Señor William Vogt, a la terminación del contracto de tres años que con autorización del Supremo ... more Señor William Vogt, a la terminación del contracto de tres años que con autorización del Supremo Gobierno celebrara con la Compañia, con el fin de que llevara a cabo estudios relativos a la mejor forma de protección de las aves guaneras y aumento de la produción de las aves guaneras. Boletín de la
Marine Ornithology 43: 133–134 (2015) Kleptoparasitism, or food piracy, is widespread among seabi... more Marine Ornithology 43: 133–134 (2015) Kleptoparasitism, or food piracy, is widespread among seabirds (Brockmann & Barnard 1979, Furness 1987), leading seabirds to adopt various strategies to avoid being parasitized. These include choice of nesting location (Nettleship 1972), changes in flight altitude and behavior when approaching the colony or nest site (Grant 1971), diving underwater to escape aerial pursuit (Grant 1971), avoiding situations in which the ratio of parasites is large relative to potential victims (Grant 1971, Blackburn et al. 2009) and decreasing the same ratio by defensively aggregating as flocks, as do other organisms (e.g. Hamilton 1971, Falconer 1976, Courchamp et al. 2002, Carbone et al. 2005). This note reports on the apparent use of the last strategy by Brown Boobies Sula leucogaster to avoid parasitism by Magnificent Frigatebirds Fregata magnificens. BROWN BOOBY SULA LEUCOGASTER GROUP SIZE AS A DEFENSE AGAINST KLEPTOPARASITISM
Millions of birds in the United States die annually due to vehicle collisions on roads. Collision... more Millions of birds in the United States die annually due to vehicle collisions on roads. Collisions may be of particular interest for species of conservation concern, such as the endangered Hawaiian goose (Nē nē), which is endemic to Hawai'i. Using a nearly 40-year dataset of Nē nē road mortality in and around Hawai'i Volcanoes National Park, we sought to answer the following research questions: 1) has Nē nē mortality changed over time? 2) are there times of the year in which mortality is greatest and does it relate to specific events in the species' lifecycle? 3) does age at mortality differ over time, space, or sex? 4) given that existing mortalities appear to occur only in certain locations, do the number of mortality events differ across these locations; 5) does mortality rate show any density dependence? and, 6) are mortality rates related to numbers of visitors or vehicles? Between 1977 and 2014, a total of 92 Nē nē died from vehicle collisions; while absolute mortality increased over this time, the mortality rate remained the same. Similarly, average age of mortality increased over time, but did not differ by location or sex. Between 1995 and 2014, Nē nē population size and mortality rates were not correlated. Mortality was greatest in November and December (breeding season) and lowest in June. Most of the mortality occurred along just three stretches of road in and around the park, with the number of mortalities split about evenly inside and outside of the park. Furthermore, Nē nē mortality was unrelated to the number of visitors or traffic volume in the park. These findings suggest vehicle collisions are a growing concern for Nē nē , but that management actions to reduce mortality can be targeted at specific road segments and times of the year.
Evolution in the Hawaiian Islands has produced a unique avian assemblage. Unfortunately, many of ... more Evolution in the Hawaiian Islands has produced a unique avian assemblage. Unfortunately, many of these bird species are highly endangered or extinct. Despite numerous and increasing threats and great effort aimed at saving endemic birds, we lack basic science necessary for understanding many species of concern. One such species is the critically endangered Puaiohi (Myadestes palmeri), a rare songbird endemic to the island of Kaua'i and the only remaining native thrush on the island. At present, the Puaiohi's breeding population is estimated to be ~500 birds restricted to the Alaka'i Wilderness Preserve. We collected demographic data from 2007-2012 and supplemented it with published sources. Using Vortex, we developed stochastic population models to represent Puaiohi population dynamics under current and potential management scenarios to determine management's potential efficacy in aiding species recovery. Management scenarios modeled included rat control, habitat imp...
The island of Kaua'i, Hawai'i has several remaining populations of endangered, endemic Hawaiian p... more The island of Kaua'i, Hawai'i has several remaining populations of endangered, endemic Hawaiian petrels (Pteradroma sandwichensis) and Newell's shearwaters (Pr�fji.nus newelli) that would be threatened by the presence of pred atory mongooses (Herpestes javrmicus). Despite over 200 putative sightings, 1 road-kill and 2 recent captures, it is not clear if mongooses actually be come established on Kaua'i. Comparing road transects on three Hawaiian is lands, we found mongooses present on O'ahu and Maui where they are known to occur and no evidence of significant populations on Kaua'i. Three popula tion scenarios are presented that would account for the three specimens, the past sightings, and the absence of sightings on our transects on Kaua'i.
The miconia (Miconia calvescens) invasion of the East Maui Watershed (EMW) started from a single ... more The miconia (Miconia calvescens) invasion of the East Maui Watershed (EMW) started from a single introduction over 40 yr ago, establishing a nascent patch network spread across 20,000 ha. In 2012, an accelerated intervention strategy was implemented utilizing the Herbicide Ballistic Technology (HBT) platform in a Hughes 500D helicopter to reduce target densities of seven nascent patches in the EMW. In a 14-mo period, a total of 48 interventions eliminated 4,029 miconia targets, with an estimated 33% increase in operations and 168% increase in recorded targets relative to the adjusted means from 2005 to 2011 data (prior to HBT adoption). This sequence of interventions covered a total net area of 1,138 ha, creating a field mosaic of overlapping search coverage (saturation) for each patch (four to eight interventions per patch). Target density reduction for each patch fit exponential decay functions (R 2 > 0.88, P < 0.05), with a majority of the target interventions spatially ass...
Nymphal Irodes sconularis Say deer ticks wcre collected at 22 narks or other natural areas on ~on... more Nymphal Irodes sconularis Say deer ticks wcre collected at 22 narks or other natural areas on ~ong Island, Nc& York, to examine the relationship betwe& tick popu- lations and geographic position, size of area, grescnce of white-tailed deer, Odocoileus virginionus (Limmerman), and numbcrs of human Lymr disease cases in acljliacent com- munities. Nymphal ticks were 93% less abundant when dew were ahsent and were also less common iu smaller natural arcas. Geographic position on Long Island was not impor- tant. Tick numbers were significantly correlated with human Lyme discasc incidence in adjacent townships. A second survey oflarval ticks from fivc areas whcm deer werc absent and six where deer were present found larvae present at four of the five sites without deer, but at only 2% of the levels found where deer were present. These results suggest that populations of I. scapularis can occur and reproduce in the absence of white-tailed decr, so that eradication of all deer would greatly...
Health on whether any sanctions should be imposed by DHHS and, if so, what they should be. As the... more Health on whether any sanctions should be imposed by DHHS and, if so, what they should be. As the biomedical and behavioral research community continues to adopt policies and procedures that deal effectively with allegations or suspicions of scientific misconduct, the OSI should find fewer occasions to conduct its own investigations. Strong institutional frameworks for dealing with scientific misconduct also will enable the PHS to focus on its primary responsibilities in this area; namely, monitoring institutional compliance with PHS policies and regulations and developing prevention and education programs. It is widely believed that scientific misconduct is not widespread. Nevertheless, even a small number of instances of scientific misconduct is unacceptable. As the steward of the vast majority of available federal awards for biomedical and behavioral research, the PHS will ensure that an effective process is in place for dealing with scientific misconduct.
The introduction of mammalian predators onto islands with terrestrially breeding seabirds can res... more The introduction of mammalian predators onto islands with terrestrially breeding seabirds can result in profoundly negative effects for breeding success and eventually for populations of the birds (e.g. Moors & Atkinson 1984). The preferred response is to remove such predators, and there are numerous successful examples (Towns et al. 1997, Nogales et al. 2004, Parkes et al. 2014). However, if complete predator removal is logistically impossible and complicated by the presence of multiple introduced predators, effective management may become more problematic. In such instances, knowledge of the relative damage contributed by each predator species may be helpful, so that limited resources can be directed at the species and management efforts that would be likely to have the greatest positive effect on seabirds and other native fauna.
Marine bird populations interact with fisheries in a variety of ways, with diverse outcomes. Eval... more Marine bird populations interact with fisheries in a variety of ways, with diverse outcomes. Evaluation of these outcomes requires a means of comparison across cases, and a means of identifying the relative importance of concomitant processes at relevant space and time scales. We describe a general quantitative framework that permits comparison of quantitative findings among studies of seabird-fisheries interactions. We then review the results of seabird-fsheries studies within this framework. We discuss the use of ad hoc ratios and dimensional analysis to make decisions about competing processes at relevant space and time scales.
When searching for prey, animals should maximize energetic gain, while minimizing energy expendit... more When searching for prey, animals should maximize energetic gain, while minimizing energy expenditure by altering their movements relative to prey availability. However, with increasing amounts of marine debris, what once may have been 'optimal' foraging strategies for top marine predators, are leading to sub-optimal diets comprised in large part of plastic. Indeed, the highly vagile Laysan albatross (Phoebastria immutabilis) which forages throughout the North Pacific, are well known for their tendency to ingest plastic. Here we examine whether Laysan albatrosses nesting on Kure Atoll and Oahu Island, 2,150 km apart, experience different levels of plastic ingestion. Twenty two geolocators were deployed on breeding adults for up to two years. Regurgitated boluses of undigestable material were also collected from chicks at each site to compare the amount of plastic vs. natural foods. Chicks from Kure Atoll were fed almost ten times the amount of plastic compared to chicks from Oahu despite boluses from both colonies having similar amounts of natural food. Tracking data indicated that adults from either colony did not have core overlapping distributions during the early half of the breeding period and that adults from Kure had a greater overlap with the putative range of the Western Garbage Patch corroborating our observation of higher plastic loads at this colony. At-sea distributions also varied throughout the year suggesting that Laysan albatrosses either adjusted their foraging behavior according to constraints on time away from the nest or to variation in resources. However, in the non-breeding season, distributional overlap was greater indicating that the energy required to reach the foraging grounds was less important than the total energy available. These results demonstrate how a marine predator that is not dispersal limited alters its foraging strategy throughout the reproductive cycle to maximize energetic gain and how this has led to differences in plastic ingestion. Citation: Young LC, Vanderlip C, Duffy DC, Afanasyev V, Shaffer SA (2009) Bringing Home the Trash: Do Colony-Based Differences in Foraging Distribution Lead to Increased Plastic Ingestion in Laysan Albatrosses? PLoS ONE 4(10): e7623.
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