Stephen Rothstein - Profile on Academia.edu (original) (raw)
Papers by Stephen Rothstein
The Condor, Aug 1, 2010
Resumen. Aunque se reconoce ampliamente que la selección de pareja por parte de las hembras de la... more Resumen. Aunque se reconoce ampliamente que la selección de pareja por parte de las hembras de las aves canoras probablemente se basa en señales multimodales como aquellas contenidas en los despliegues audiovisuales de canto, algunas dificultades de procedimiento han restringido los estudios sobre la selección de pareja en estas aves principalmente a las señales acüsticas. En el presente estudio, utilizamos grabaciones audiovisuales de Molothrus ater para evaluar las respuestas sexuales de las hembras a los despliegues de canto de los machos. Usando los despliegues de solicitud de cópula de hembras tratadas con estradiol (n 9), encontramos que la reproducción de audiovisuales que mostraban machos realizando despliegues de canto con las alas abiertas fueron mucho más estimulantes para las hembras que la presentación de cantos acompañados de videos de machos que no estaban desplegando y que la presentación de sólo cantos. Los resultados de este estudio demostraron claramente que el estímulo visual del despliegue de alas abiertas en particular, y no sólo el estímulo visual de un macho coespecífico en general, estimula la máxima respuesta observada entre las hembras. En M. ater, las preferencias sexuales de las hembras por los cantos reveladas por estudios de los despliegues de solicitud de cópula varían en paralelo con el éxito de apareamiento de los machos, de modo que nuestros resultados probablemente reflejan un efecto de los despliegues visuales sobre el éxito de apareamiento de los machos silvestres.
Host Defenses against Cowbird (Molothrus spp.) Parasitism: Implications for Cowbird Management
Ornithological Monographs, 2005
ABSTRACT Brown-headed Cowbird (Molothrus ater; hereafter "cowbird") parasitism ... more ABSTRACT Brown-headed Cowbird (Molothrus ater; hereafter "cowbird") parasitism is costly to host fitness, especially for smaller hosts whose nestlings have to compete with larger cowbird nestlings that often hatch earlier. Those fitness costs select for a variety of host defenses, including inconspicuous nests, aggression toward cowbirds, deserting parasitized nests, burying cowbird eggs, and ejecting cowbird eggs from nests. Egg ejection is the most effective defense against parasitism, but there are only 30 hosts known to regularly eject cowbird eggs. Evolutionary lag is the most likely reason that relatively few hosts demonstrate ejection. However, once ejection evolves in a host, some evidence indicates that it is maintained for long periods of time, even in the absence of brood parasitism-which suggests that host communities are becoming increasingly resistant to parasitism over time. With progressively fewer naive hosts to exploit, cowbirds may specialize on just a few host species. Retention of host defenses is also important because cowbirds were probably more common in the past, when mammalian megafauna were present. As a result, not every newly exposed host population requires cowbird control programs, because many have maintained defenses after inheriting them from ancestors that were exposed to parasitism, making them well defended against new bouts of parasitism. Several hosts that are currently the focus of control programs demonstrate defenses against parasitism, and their populations have increased. We suggest that the time has come to relax control of some of those species, to determine whether they can sustain their populations in the presence of parasitism and to allow their natural defenses to increase, so that they will not be perpetually dependent on human intervention. /// El parasitismo de Molothrus ater es costoso en términos de la adecuación de sus hospederos, en especial de aquellos de pequeño tamaño cuyos pichones deben competir con los pichones de Molothrus más grandes que en general eclosionan más temprano. Estos costos en adecuación seleccionan en favor de varias defensas por parte de los hopederos, que incluyen: nidos inconspicuos, agredir a los Molothrus, abandonar los nidos parasitados, y enterrar o rechazar los huevos de M. ater del nido. El rechazo del huevo es la defensa más efectiva contra el parasitismo, pero se sabe que sólo 30 especies de hospederos rechazan regularmente los huevos de M. ater. El retraso evolutivo es la causa más probable para explicar porqué tan bajo número de hospederos demuestran rechazo. Sin embargo, una vez que el rechazo evoluciona en un hospedero, existe evidencia indicando que es mantenido por largo tiempo, aún en ausencia de parasitismo de cría. Este último fenómeno sugeriría que las comunidades de hospederos se estarían volviendo cada vez más resistentes al parasitismo. Con una progresión hacia un menor número de hospederos "inocentes" para explotar, los Molothrus pueden especializarse en unas pocas especies hospederas. La retención de las defensas en los hospederos es también importante porque los Molothrus fueron probablemente más abundantes en el pasado, cuando la megafauna de mamíferos estaba presente. En consecuencia, no todas las especies de hospederos recientemente expuestas al parasitismo por Molothrus requerirían de programas de manejo de Molothrus. Muchas de ellas podrían mantener defensas que habrían heredado de ancestros que si estuvieron expuestos al parasitismo, haciendo que estuvieran bien defendidas contra nuevos eventos de parasitismo. Varios hospederos que actualmente son centro de programas de control demostraron defensas contra el parasitismo, y sus poblaciones se han incrementado. Nosotros sugerimos que ha llegado el tiempo de relajar el control sobre algunas de dichas especies, y de esta manera determinar si pueden mantener sus poblaciones en presencia del parasitismo. Al mismo tiempo, se estaría permitiendo que sus defensas naturales se incrementaran, y de este modo, que no dependieran perpetuamente de la intervención humana.
Subspecies and Dialects in the Brown-Headed Cowbird
Behavioral Ecology, Sep 25, 2015
Yellow warblers, Setophaga petechia, respond to brood parasitic brown-headed cowbirds, Molothrus ... more Yellow warblers, Setophaga petechia, respond to brood parasitic brown-headed cowbirds, Molothrus ater, by giving "seet" alarm calls and rushing to protect their nests. These responses are typically given in populations sympatric with cowbirds, but rarely in allopatric populations. Whether the lower expression in allopatry has a genetic basis or instead could be explained by behavioral plasticity has not been investigated. We found that warblers exposed to cowbirds in Montana (sympatric) responded significantly more often to cowbird models with seet calls (85.7%) and nest protection behavior (80.0%) than conspecifics breeding in long-term isolation from cowbirds in Alaska (allopatric, 27.3% and 16.7%, respectively). Warblers breeding in Idaho, which were locally isolated from cowbirds (naive) but presumed to be genetically similar to nearby parasitized warblers, were significantly less likely than sympatric warblers to respond to cowbird models with seet calls (30.3%) and nest protection (17.3%). The lower responsiveness of naive warblers implies behavioral plasticity in trait expression, indicating that the lower responsiveness of allopatric warblers relative to sympatric warblers could be explained entirely by plasticity. The lower expression of these defenses in the absence of cowbirds may contribute to their persistence by minimizing potentially costly recognition errors.
1. Introduction
Ecology and Management of Cowbirds and Their Hosts, 2000
Recommendations for cowbird management in recovery efforts for the Southwestern Willow Flycatcher
Studies in Avian Biology
The incidence of Brown-headed Cowbird (Molothrus ater) parasitism of Southwestern Willow Flycatch... more The incidence of Brown-headed Cowbird (Molothrus ater) parasitism of Southwestern Willow Flycatchers (Empidonax traillii extimus) is highly variable, ranging from less than 10% at some sites to over 50% at others. Parasitism usually results in complete loss of flycatcher reproductive output because most parasitized nests are deserted or fledge only a cowbird, although birds that desert often renest. Despite the reduced reproductive output from individual flycatcher nests, it is not clear that cowbird parasitism affects Southwestern Willow Flycatcher population sizes. Cowbird control reduces parasitism rates and increases the reproductive output of Southwestern Willow Flycatchers, but there is no firm evidence yet that it has resulted in any increases of flycatcher populations or forestalled declines, suggesting that populations may be limited by other factors, such as habitat. Cowbird control may nevertheless be an appropriate management option because some populations may benefit a...
Clutch size determination, egg size, and eggshell thickness in the Pie-billed Grebe
The Auk, Apr 1, 1977
Nest Parasitism
Encyclopedia of Biodiversity, 2013
An agonistic visual signal during birdsong: Bill wiping in multimodal song displays by the male Brown-headed Cowbird (Molothrus ater)
The Wilson Journal of Ornithology
Human–Wildlife Interactions, 2020
The brown-headed cowbird (Molothrus ater; cowbird) is unique among North American blackbirds (Ict... more The brown-headed cowbird (Molothrus ater; cowbird) is unique among North American blackbirds (Icteridae) because it is managed to mitigate the negative effects on endangered songbirds and economic losses in agricultural crops. Cowbird brood parasitism can further affect species that are considered threatened or endangered due to anthropogenic land uses. Historically, cowbirds have often been culled without addressing ultimate causes of songbird population declines. Similar to other North American blackbirds, cowbirds depredate agricultural crops, albeit at a lower rate reported for other blackbird species. Conflicting information exists on the extent of agricultural damage caused by cowbirds and the effectiveness of mitigation measures for application to management. In this paper, we reviewed the progress that has been made in cowbird management from approximately 2005 to 2020 in relation to endangered species. We also reviewed losses to the rice (Oryza sativa) crop attributed to co...
Experiments on Defenses Cedar Waxwings Use against Cowbird Parasitism
Studies in Avian Biology is a series of works too long for The Condor, published at irregular int... more Studies in Avian Biology is a series of works too long for The Condor, published at irregular intervals by the Cooper Ornithological Society. Manuscripts for consideration should be submitted to the editor. Style and format should follow those of previous issues. Price $18.00 including postage and handling. All orders cash in advance; make checks payable to Cooper Ornithological Society. Send orders to Cooper Ornithological Society, % Western Foundation of Vertebrate Zoology,
Persistence of host defence behaviour in the absence of avian brood
ABSTRACT The fate of host defensive behaviour in the absence of selection from brood parasitism i... more ABSTRACT The fate of host defensive behaviour in the absence of selection from brood parasitism is critical to long-term host-parasite coevolution. We investigated whether New World Bohemian waxwings Bombycilla garrulus that are allopatric from brown-headed cowbird Molothrus ater and common cuckoo Cuculus canorus parasitism have retained egg rejection behaviour. We found that egg rejection was expressed by 100 per cent of Bohemian waxwings. Our phylogeny revealed that Bohemian and Japanese waxwings Bombycilla japonica were sister taxa, and this clade was sister to the cedar waxwing Bombycilla cedrorum. In addition, there was support for a split between Old and New World Bohemian waxwings. Our molecular clock estimates suggest that egg rejection may have been retained for 2.8-3.0 Myr since New World Bohemian waxwings inherited it from their common ancestor with the rejecter cedar waxwings. These results support the 'single trajectory' model of host-brood parasite coevolution that once hosts evolve defences, they are retained, forcing parasites to become more specialized over time.
7. The Structure and Function of Cowbird Vocalizations and the Use of Playbacks to Enhance Cowbird Detectability: Relations to Potential Censusing Biases
Ecology and Management of Cowbirds and Their Hosts, 2000
36. Introduction
Ecology and Management of Cowbirds and Their Hosts, 2000
Behavioral differences among sex and age classes of the Brown-headed Cowbird and their relation to the efficacy of a control program
The Wilson Bulletin, 1987
Notes, 2002
Recovery Plans delineate reasonable actions that are believed to be required to recover and/or pr... more Recovery Plans delineate reasonable actions that are believed to be required to recover and/or protect listed species. Plans are published by the U.S. Fish and Wildlife Service, sometimes prepared with the assistance of recovery team s, contractors, State agencies, and others. Objectives will be attained and any necessary funds made available subject to budgetary and other constraints affecting the parties involved, as well as the need to address other priorities. Recovery plans do not necessarily represent the views nor the official positions or approval of any individuals or agencies involved in the plan formulation, other than the U.S. Fish and Wildlife Service. They represent the official position of the U.S. Fish and Wildlife Service only after they have been signed by the Regional Director or Director as approved. Approved Recovery plans are subject to modification as dictated by new findings, changes in species status, and the completion of recovery tasks. Some of the techniques outlined for recovery efforts in this plan are completely new regarding this subspecies. Therefore, the cost and time estimates are approximations.
The Auk, 2005
, infanticide, and male-female confl icts over parental care. This is one of a number of excellen... more , infanticide, and male-female confl icts over parental care. This is one of a number of excellent recent books in evolutionary biology (e.g. Olivia Judson's Dr. Tatiana's Sex Advice to All Creation and Marlene Zuk's Sexual Selections: What We Can and Can't Learn About Sex from Animals) that are targeted primarily at a general readership but are suffi ciently well referenced to be useful to specialists. The 15 chapters of More Than Kin and Less Than Kind include 287 superscripted endnotes and a 19-page Works Cited section that encompasses nearly 300 references. Even avian biologists and behavioral ecologists who are familiar with the topics considered in the book will learn plenty from Mock's engaging survey of the fi eld. The book is beautifully wriĴ en. As someone who has spent much of his professional life teaching evolutionary biology to undergraduates, I found myself pausing frequently to admire Mock's obvious abilities as a teacher. With patient but lively prose, Mock skillfully meshes lucid explanations of evolutionary theory with key natural-history observations, crucial experimental details, perceptive historical context, and amusing anecdotes. Mock is a keen observer, not only of the egrets and herons he has watched for so many years, but also of the nature of fi eld biology (e.g. "moments of great exhilaration and discovery are rare outposts in the vast deserts of labor and tedium") and scientifi c discovery (e.g. "scientifi c knowledge is nothing if not ephemeral, and only nonscientists misinterpret that as a fl aw"). Reading More Than Kin and Less Than Kind is like taking a course from a giĞ ed teacher-an altogether enlightening, inspiring, and enjoyable experience. Readers may quibble with some of Mock's analyses. For example, his view that Robert
The Condor, Aug 1, 2010
Resumen. Aunque se reconoce ampliamente que la selección de pareja por parte de las hembras de la... more Resumen. Aunque se reconoce ampliamente que la selección de pareja por parte de las hembras de las aves canoras probablemente se basa en señales multimodales como aquellas contenidas en los despliegues audiovisuales de canto, algunas dificultades de procedimiento han restringido los estudios sobre la selección de pareja en estas aves principalmente a las señales acüsticas. En el presente estudio, utilizamos grabaciones audiovisuales de Molothrus ater para evaluar las respuestas sexuales de las hembras a los despliegues de canto de los machos. Usando los despliegues de solicitud de cópula de hembras tratadas con estradiol (n 9), encontramos que la reproducción de audiovisuales que mostraban machos realizando despliegues de canto con las alas abiertas fueron mucho más estimulantes para las hembras que la presentación de cantos acompañados de videos de machos que no estaban desplegando y que la presentación de sólo cantos. Los resultados de este estudio demostraron claramente que el estímulo visual del despliegue de alas abiertas en particular, y no sólo el estímulo visual de un macho coespecífico en general, estimula la máxima respuesta observada entre las hembras. En M. ater, las preferencias sexuales de las hembras por los cantos reveladas por estudios de los despliegues de solicitud de cópula varían en paralelo con el éxito de apareamiento de los machos, de modo que nuestros resultados probablemente reflejan un efecto de los despliegues visuales sobre el éxito de apareamiento de los machos silvestres.
Host Defenses against Cowbird (Molothrus spp.) Parasitism: Implications for Cowbird Management
Ornithological Monographs, 2005
ABSTRACT Brown-headed Cowbird (Molothrus ater; hereafter "cowbird") parasitism ... more ABSTRACT Brown-headed Cowbird (Molothrus ater; hereafter "cowbird") parasitism is costly to host fitness, especially for smaller hosts whose nestlings have to compete with larger cowbird nestlings that often hatch earlier. Those fitness costs select for a variety of host defenses, including inconspicuous nests, aggression toward cowbirds, deserting parasitized nests, burying cowbird eggs, and ejecting cowbird eggs from nests. Egg ejection is the most effective defense against parasitism, but there are only 30 hosts known to regularly eject cowbird eggs. Evolutionary lag is the most likely reason that relatively few hosts demonstrate ejection. However, once ejection evolves in a host, some evidence indicates that it is maintained for long periods of time, even in the absence of brood parasitism-which suggests that host communities are becoming increasingly resistant to parasitism over time. With progressively fewer naive hosts to exploit, cowbirds may specialize on just a few host species. Retention of host defenses is also important because cowbirds were probably more common in the past, when mammalian megafauna were present. As a result, not every newly exposed host population requires cowbird control programs, because many have maintained defenses after inheriting them from ancestors that were exposed to parasitism, making them well defended against new bouts of parasitism. Several hosts that are currently the focus of control programs demonstrate defenses against parasitism, and their populations have increased. We suggest that the time has come to relax control of some of those species, to determine whether they can sustain their populations in the presence of parasitism and to allow their natural defenses to increase, so that they will not be perpetually dependent on human intervention. /// El parasitismo de Molothrus ater es costoso en términos de la adecuación de sus hospederos, en especial de aquellos de pequeño tamaño cuyos pichones deben competir con los pichones de Molothrus más grandes que en general eclosionan más temprano. Estos costos en adecuación seleccionan en favor de varias defensas por parte de los hopederos, que incluyen: nidos inconspicuos, agredir a los Molothrus, abandonar los nidos parasitados, y enterrar o rechazar los huevos de M. ater del nido. El rechazo del huevo es la defensa más efectiva contra el parasitismo, pero se sabe que sólo 30 especies de hospederos rechazan regularmente los huevos de M. ater. El retraso evolutivo es la causa más probable para explicar porqué tan bajo número de hospederos demuestran rechazo. Sin embargo, una vez que el rechazo evoluciona en un hospedero, existe evidencia indicando que es mantenido por largo tiempo, aún en ausencia de parasitismo de cría. Este último fenómeno sugeriría que las comunidades de hospederos se estarían volviendo cada vez más resistentes al parasitismo. Con una progresión hacia un menor número de hospederos "inocentes" para explotar, los Molothrus pueden especializarse en unas pocas especies hospederas. La retención de las defensas en los hospederos es también importante porque los Molothrus fueron probablemente más abundantes en el pasado, cuando la megafauna de mamíferos estaba presente. En consecuencia, no todas las especies de hospederos recientemente expuestas al parasitismo por Molothrus requerirían de programas de manejo de Molothrus. Muchas de ellas podrían mantener defensas que habrían heredado de ancestros que si estuvieron expuestos al parasitismo, haciendo que estuvieran bien defendidas contra nuevos eventos de parasitismo. Varios hospederos que actualmente son centro de programas de control demostraron defensas contra el parasitismo, y sus poblaciones se han incrementado. Nosotros sugerimos que ha llegado el tiempo de relajar el control sobre algunas de dichas especies, y de esta manera determinar si pueden mantener sus poblaciones en presencia del parasitismo. Al mismo tiempo, se estaría permitiendo que sus defensas naturales se incrementaran, y de este modo, que no dependieran perpetuamente de la intervención humana.
Subspecies and Dialects in the Brown-Headed Cowbird
Behavioral Ecology, Sep 25, 2015
Yellow warblers, Setophaga petechia, respond to brood parasitic brown-headed cowbirds, Molothrus ... more Yellow warblers, Setophaga petechia, respond to brood parasitic brown-headed cowbirds, Molothrus ater, by giving "seet" alarm calls and rushing to protect their nests. These responses are typically given in populations sympatric with cowbirds, but rarely in allopatric populations. Whether the lower expression in allopatry has a genetic basis or instead could be explained by behavioral plasticity has not been investigated. We found that warblers exposed to cowbirds in Montana (sympatric) responded significantly more often to cowbird models with seet calls (85.7%) and nest protection behavior (80.0%) than conspecifics breeding in long-term isolation from cowbirds in Alaska (allopatric, 27.3% and 16.7%, respectively). Warblers breeding in Idaho, which were locally isolated from cowbirds (naive) but presumed to be genetically similar to nearby parasitized warblers, were significantly less likely than sympatric warblers to respond to cowbird models with seet calls (30.3%) and nest protection (17.3%). The lower responsiveness of naive warblers implies behavioral plasticity in trait expression, indicating that the lower responsiveness of allopatric warblers relative to sympatric warblers could be explained entirely by plasticity. The lower expression of these defenses in the absence of cowbirds may contribute to their persistence by minimizing potentially costly recognition errors.
1. Introduction
Ecology and Management of Cowbirds and Their Hosts, 2000
Recommendations for cowbird management in recovery efforts for the Southwestern Willow Flycatcher
Studies in Avian Biology
The incidence of Brown-headed Cowbird (Molothrus ater) parasitism of Southwestern Willow Flycatch... more The incidence of Brown-headed Cowbird (Molothrus ater) parasitism of Southwestern Willow Flycatchers (Empidonax traillii extimus) is highly variable, ranging from less than 10% at some sites to over 50% at others. Parasitism usually results in complete loss of flycatcher reproductive output because most parasitized nests are deserted or fledge only a cowbird, although birds that desert often renest. Despite the reduced reproductive output from individual flycatcher nests, it is not clear that cowbird parasitism affects Southwestern Willow Flycatcher population sizes. Cowbird control reduces parasitism rates and increases the reproductive output of Southwestern Willow Flycatchers, but there is no firm evidence yet that it has resulted in any increases of flycatcher populations or forestalled declines, suggesting that populations may be limited by other factors, such as habitat. Cowbird control may nevertheless be an appropriate management option because some populations may benefit a...
Clutch size determination, egg size, and eggshell thickness in the Pie-billed Grebe
The Auk, Apr 1, 1977
Nest Parasitism
Encyclopedia of Biodiversity, 2013
An agonistic visual signal during birdsong: Bill wiping in multimodal song displays by the male Brown-headed Cowbird (Molothrus ater)
The Wilson Journal of Ornithology
Human–Wildlife Interactions, 2020
The brown-headed cowbird (Molothrus ater; cowbird) is unique among North American blackbirds (Ict... more The brown-headed cowbird (Molothrus ater; cowbird) is unique among North American blackbirds (Icteridae) because it is managed to mitigate the negative effects on endangered songbirds and economic losses in agricultural crops. Cowbird brood parasitism can further affect species that are considered threatened or endangered due to anthropogenic land uses. Historically, cowbirds have often been culled without addressing ultimate causes of songbird population declines. Similar to other North American blackbirds, cowbirds depredate agricultural crops, albeit at a lower rate reported for other blackbird species. Conflicting information exists on the extent of agricultural damage caused by cowbirds and the effectiveness of mitigation measures for application to management. In this paper, we reviewed the progress that has been made in cowbird management from approximately 2005 to 2020 in relation to endangered species. We also reviewed losses to the rice (Oryza sativa) crop attributed to co...
Experiments on Defenses Cedar Waxwings Use against Cowbird Parasitism
Studies in Avian Biology is a series of works too long for The Condor, published at irregular int... more Studies in Avian Biology is a series of works too long for The Condor, published at irregular intervals by the Cooper Ornithological Society. Manuscripts for consideration should be submitted to the editor. Style and format should follow those of previous issues. Price $18.00 including postage and handling. All orders cash in advance; make checks payable to Cooper Ornithological Society. Send orders to Cooper Ornithological Society, % Western Foundation of Vertebrate Zoology,
Persistence of host defence behaviour in the absence of avian brood
ABSTRACT The fate of host defensive behaviour in the absence of selection from brood parasitism i... more ABSTRACT The fate of host defensive behaviour in the absence of selection from brood parasitism is critical to long-term host-parasite coevolution. We investigated whether New World Bohemian waxwings Bombycilla garrulus that are allopatric from brown-headed cowbird Molothrus ater and common cuckoo Cuculus canorus parasitism have retained egg rejection behaviour. We found that egg rejection was expressed by 100 per cent of Bohemian waxwings. Our phylogeny revealed that Bohemian and Japanese waxwings Bombycilla japonica were sister taxa, and this clade was sister to the cedar waxwing Bombycilla cedrorum. In addition, there was support for a split between Old and New World Bohemian waxwings. Our molecular clock estimates suggest that egg rejection may have been retained for 2.8-3.0 Myr since New World Bohemian waxwings inherited it from their common ancestor with the rejecter cedar waxwings. These results support the 'single trajectory' model of host-brood parasite coevolution that once hosts evolve defences, they are retained, forcing parasites to become more specialized over time.
7. The Structure and Function of Cowbird Vocalizations and the Use of Playbacks to Enhance Cowbird Detectability: Relations to Potential Censusing Biases
Ecology and Management of Cowbirds and Their Hosts, 2000
36. Introduction
Ecology and Management of Cowbirds and Their Hosts, 2000
Behavioral differences among sex and age classes of the Brown-headed Cowbird and their relation to the efficacy of a control program
The Wilson Bulletin, 1987
Notes, 2002
Recovery Plans delineate reasonable actions that are believed to be required to recover and/or pr... more Recovery Plans delineate reasonable actions that are believed to be required to recover and/or protect listed species. Plans are published by the U.S. Fish and Wildlife Service, sometimes prepared with the assistance of recovery team s, contractors, State agencies, and others. Objectives will be attained and any necessary funds made available subject to budgetary and other constraints affecting the parties involved, as well as the need to address other priorities. Recovery plans do not necessarily represent the views nor the official positions or approval of any individuals or agencies involved in the plan formulation, other than the U.S. Fish and Wildlife Service. They represent the official position of the U.S. Fish and Wildlife Service only after they have been signed by the Regional Director or Director as approved. Approved Recovery plans are subject to modification as dictated by new findings, changes in species status, and the completion of recovery tasks. Some of the techniques outlined for recovery efforts in this plan are completely new regarding this subspecies. Therefore, the cost and time estimates are approximations.
The Auk, 2005
, infanticide, and male-female confl icts over parental care. This is one of a number of excellen... more , infanticide, and male-female confl icts over parental care. This is one of a number of excellent recent books in evolutionary biology (e.g. Olivia Judson's Dr. Tatiana's Sex Advice to All Creation and Marlene Zuk's Sexual Selections: What We Can and Can't Learn About Sex from Animals) that are targeted primarily at a general readership but are suffi ciently well referenced to be useful to specialists. The 15 chapters of More Than Kin and Less Than Kind include 287 superscripted endnotes and a 19-page Works Cited section that encompasses nearly 300 references. Even avian biologists and behavioral ecologists who are familiar with the topics considered in the book will learn plenty from Mock's engaging survey of the fi eld. The book is beautifully wriĴ en. As someone who has spent much of his professional life teaching evolutionary biology to undergraduates, I found myself pausing frequently to admire Mock's obvious abilities as a teacher. With patient but lively prose, Mock skillfully meshes lucid explanations of evolutionary theory with key natural-history observations, crucial experimental details, perceptive historical context, and amusing anecdotes. Mock is a keen observer, not only of the egrets and herons he has watched for so many years, but also of the nature of fi eld biology (e.g. "moments of great exhilaration and discovery are rare outposts in the vast deserts of labor and tedium") and scientifi c discovery (e.g. "scientifi c knowledge is nothing if not ephemeral, and only nonscientists misinterpret that as a fl aw"). Reading More Than Kin and Less Than Kind is like taking a course from a giĞ ed teacher-an altogether enlightening, inspiring, and enjoyable experience. Readers may quibble with some of Mock's analyses. For example, his view that Robert