Each year at least a billion birds migrate down the west coast of North America along what is kno... more Each year at least a billion birds migrate down the west coast of North America along what is known as the Pacific Flyway ([ 1 ][1]). For the aquatic species, large, open bodies of water are important oases. For more than a century, the Salton Sea in southern California has been a vital component of
The availability of suitable roosts influences the distribution and abundance of bats. Quantifyin... more The availability of suitable roosts influences the distribution and abundance of bats. Quantifying roosting requirements is a necessary step toward effectively monitoring, managing, and conserving bats. Our objectives were to locate and characterize the natural, daytime summer roosts ...
Feeding is an aspect of animal performance that has clear consequences for individual fitness and... more Feeding is an aspect of animal performance that has clear consequences for individual fitness and morphological evolution. Hummingbirds (Family Trochilidae) are an excellent group for the study of feeding performance because they are a speciose family of small, hovering, nectar specialists evolved from insectivorous ancestors. My dissertation research explored the role of insectivory in the evolution and ecology of hummingbirds. Here I begin with a review of the interaction of diet, morphology, physiology, and ecology to illustrate the importance of insectivory to all aspects of hummingbird biology. ^ In the second chapter, I characterize variation in hummingbird beak morphology based on museum specimens and examine this variation with respect to diet and ecology in a phylogenetic context. I find that hummingbird beak length is variable but that the distal dimensions of hummingbird beaks do not vary with respect to beak width and depth. This narrowness in beak dimension is presumably driven by the physical demands of nectar transport, but may hinder effective arthropod capture and transport, representing a potential tradeoff in beak function. ^ In chapters three and four, I investigate how hummingbirds catch and consume arthropod prey. I use high speed videography to document the feeding behaviors, performance, and kinematics of six hummingbird species. I discover that hummingbirds use a novel form of dorsoventral mandibular flexion during aerial arthropod capture. I examine the mechanics of dorsoventral mandibular flexion and discuss the consequences of kinesis for arthropod capture and transport. This study of feeding mechanics and kinematics looks at variation in feeding performance at the individual and species level in a group of birds with two distinct modes of feeding to provide insight into how morphology, behavior, and phylogeny contribute to the evolution of specialization in diet and trophic structures.
Migratory birds have been declining, in some cases rapidly, for the past 30 years due in part to ... more Migratory birds have been declining, in some cases rapidly, for the past 30 years due in part to loss of habitat and habitat fragmentation. Forestry for the Birds provides information connecting sustainable forestry management practices to the habitat needs and natural history of birds, creating an accessible way for private forest owners to “let forest forests function as forests and keep common birds common”. The program brings together foresters, landowners, academics, non-profits, and state and federal agencies to find management solutions that support bird populations and promote sustainable forestry on working lands. This program has been funded in Washington County by the Tualatin Soil and Watershed Council from 2019-2022. Here we outline the goals of the program, its methods, and how to get involved
Our analysis is based on 496 Anna's Hummingbirds (146 museum specimens, 350 banding records) ... more Our analysis is based on 496 Anna's Hummingbirds (146 museum specimens, 350 banding records) and 218 Rufous Hummingbirds (131 museum specimens, 87 banding records). Specimens of all Anna's and most Rufous Hummingbirds were from the collections at the California Academy of Sciences (CAS), Moore Laboratory of Zoology (MLZ), Museum of Vertebrate Zoology (MVZ), and PRBO. To augment our sample of fall and winter Rufous Hummingbirds (collected in Mexico), we also examined specimens at the Natural History Museum of Los Angeles County (LACM), San Diego Natural History Museum (SDNHM), and Western Foundation of Vertebrate Zoology (WFVZ). Specimens of Anna's Hummingbirds were taken from throughout the species' breeding range, although a majority __
Our analysis is based on 496 Anna's Hummingbirds (146 museum specimens, 350 banding records)... more Our analysis is based on 496 Anna's Hummingbirds (146 museum specimens, 350 banding records) and 218 Rufous Hummingbirds (131 museum specimens, 87 banding records). Specimens of all Anna's and most Rufous Hummingbirds were from the collections at the California Academy of Sciences (CAS), Moore Laboratory of Zoology (MLZ), Museum of Vertebrate Zoology (MVZ), and PRBO. To augment our sample of fall and winter Rufous Hummingbirds (collected in Mexico), we also examined specimens at the Natural History Museum of Los Angeles County (LACM), San Diego Natural History Museum (SDNHM), and Western Foundation of Vertebrate Zoology (WFVZ). Specimens of Anna's Hummingbirds were taken from throughout the species' breeding range, although a majority __
Each year at least a billion birds migrate down the west coast of North America along what is kno... more Each year at least a billion birds migrate down the west coast of North America along what is known as the Pacific Flyway ([ 1 ][1]). For the aquatic species, large, open bodies of water are important oases. For more than a century, the Salton Sea in southern California has been a vital component of
The availability of suitable roosts influences the distribution and abundance of bats. Quantifyin... more The availability of suitable roosts influences the distribution and abundance of bats. Quantifying roosting requirements is a necessary step toward effectively monitoring, managing, and conserving bats. Our objectives were to locate and characterize the natural, daytime summer roosts ...
Feeding is an aspect of animal performance that has clear consequences for individual fitness and... more Feeding is an aspect of animal performance that has clear consequences for individual fitness and morphological evolution. Hummingbirds (Family Trochilidae) are an excellent group for the study of feeding performance because they are a speciose family of small, hovering, nectar specialists evolved from insectivorous ancestors. My dissertation research explored the role of insectivory in the evolution and ecology of hummingbirds. Here I begin with a review of the interaction of diet, morphology, physiology, and ecology to illustrate the importance of insectivory to all aspects of hummingbird biology. ^ In the second chapter, I characterize variation in hummingbird beak morphology based on museum specimens and examine this variation with respect to diet and ecology in a phylogenetic context. I find that hummingbird beak length is variable but that the distal dimensions of hummingbird beaks do not vary with respect to beak width and depth. This narrowness in beak dimension is presumably driven by the physical demands of nectar transport, but may hinder effective arthropod capture and transport, representing a potential tradeoff in beak function. ^ In chapters three and four, I investigate how hummingbirds catch and consume arthropod prey. I use high speed videography to document the feeding behaviors, performance, and kinematics of six hummingbird species. I discover that hummingbirds use a novel form of dorsoventral mandibular flexion during aerial arthropod capture. I examine the mechanics of dorsoventral mandibular flexion and discuss the consequences of kinesis for arthropod capture and transport. This study of feeding mechanics and kinematics looks at variation in feeding performance at the individual and species level in a group of birds with two distinct modes of feeding to provide insight into how morphology, behavior, and phylogeny contribute to the evolution of specialization in diet and trophic structures.
Migratory birds have been declining, in some cases rapidly, for the past 30 years due in part to ... more Migratory birds have been declining, in some cases rapidly, for the past 30 years due in part to loss of habitat and habitat fragmentation. Forestry for the Birds provides information connecting sustainable forestry management practices to the habitat needs and natural history of birds, creating an accessible way for private forest owners to “let forest forests function as forests and keep common birds common”. The program brings together foresters, landowners, academics, non-profits, and state and federal agencies to find management solutions that support bird populations and promote sustainable forestry on working lands. This program has been funded in Washington County by the Tualatin Soil and Watershed Council from 2019-2022. Here we outline the goals of the program, its methods, and how to get involved
Our analysis is based on 496 Anna's Hummingbirds (146 museum specimens, 350 banding records) ... more Our analysis is based on 496 Anna's Hummingbirds (146 museum specimens, 350 banding records) and 218 Rufous Hummingbirds (131 museum specimens, 87 banding records). Specimens of all Anna's and most Rufous Hummingbirds were from the collections at the California Academy of Sciences (CAS), Moore Laboratory of Zoology (MLZ), Museum of Vertebrate Zoology (MVZ), and PRBO. To augment our sample of fall and winter Rufous Hummingbirds (collected in Mexico), we also examined specimens at the Natural History Museum of Los Angeles County (LACM), San Diego Natural History Museum (SDNHM), and Western Foundation of Vertebrate Zoology (WFVZ). Specimens of Anna's Hummingbirds were taken from throughout the species' breeding range, although a majority __
Our analysis is based on 496 Anna's Hummingbirds (146 museum specimens, 350 banding records)... more Our analysis is based on 496 Anna's Hummingbirds (146 museum specimens, 350 banding records) and 218 Rufous Hummingbirds (131 museum specimens, 87 banding records). Specimens of all Anna's and most Rufous Hummingbirds were from the collections at the California Academy of Sciences (CAS), Moore Laboratory of Zoology (MLZ), Museum of Vertebrate Zoology (MVZ), and PRBO. To augment our sample of fall and winter Rufous Hummingbirds (collected in Mexico), we also examined specimens at the Natural History Museum of Los Angeles County (LACM), San Diego Natural History Museum (SDNHM), and Western Foundation of Vertebrate Zoology (WFVZ). Specimens of Anna's Hummingbirds were taken from throughout the species' breeding range, although a majority __
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