Unlike mammals, where females live longer than males, the pattern is reversed in many species of birds. On average, female birds have lower annual survival than males, amounting to an overall shorter lifespan. I modeled survival of sexes separately within species using banding data of 92 species from the Institute for Bird Populations. We found that in 4 of 9 families of North American passerines (figure, left), survival rates are significantly lower for female than male birds of the same species. Early exploration of mechanisms suggest that (1) higher female dispersal costs, (2) higher male social dominance, and (3) homogametic advantage in males may contribute to these survival differences. I would like to explore these hypotheses in greater detail, as well as expand sex-specific survival modeling to additional species, in future work. In press, Proceedings B.

Neotropical migrants come together to breed in the North American spring and summer, but they spend much of their year foraging on nonbreeding grounds. During this time, females and males sometimes use different habitats due to social dominance and/or differences in habitat preference. This pattern is understudied in general, so part of my research uncovers sex-specific habitats that female birds use in the nonbreeding season. Ultimately, fully protecting the places both sexes use is critical for conservation of the species. Photo: Nashville Warbler. Wendy Miller, Flickr/CC BY-NC-ND 2.0

Why the focus on female birds? What's sex got to do with conservation? Sex governs many aspects of biology, including survival, dispersal, reproductive roles, vocalizations, habitat use. Because of this, sexes of the same specifies can be impacted differently by climate change. Female birds tend to be more inconspicuous and are understudied. There might be knowledge gaps about the places we conserve if we overlook females. In our paper, we argue that including females is important in the study of ecology and conservation of birds. Potential solutions for doing so include training observers to recognize female traits, using more field methods that increase the detection of female birds (e.g. catching birds during the migration season, using DNA to determine sex), broadening geographical regions of study and recruiting a diverse group of scientists to help equalize the field of ornithological research. Wu et al. 2025. A focus on females can improve science and conservation. IBIS.

Science is the pursuit of knowledge, while conservation is rooted in socio-economic factors in the real world. The two fields are interdependent, but there is often a gap between them. I am deeply interested in conservation-based research, whether it's understanding how to manage for species after a burn, how newly introduced species affect systems, or how to act effectively in a rapidly changing world. At the center of this is equity — conservation that protects land and biota without regard to the communities that steward them is not equitable. My colleagues and I have explored nature-based solutions that offer co-benefits for both ecosystems and human communities, as well as strategies for bridging the gap between science and management.  

My colleagues and I sought to project how changing climate conditions may change the range of North American birds using species distribution modeling. They then worked with the National Park Service, Parks Canada, and U.S. Fish and Wildlife Service to create projected species composition lists at each jurisdiction unit. This figure shows which U.S. national parks are projected to see low change, intermediate change, high colonization, high extirpation, or high overall turnover in bird species.

Although I have never gotten to see one, I worked on the awesome, elusive Great Gray Owl and contribute to their Conservation Strategy in California. Great Gray Owls were always thought to nest in mid elevation Sierra Nevada conifer trees, but a surprising diversity of trees were used. Out of 56 known nests, 31 were found at <1500 m and one-third were in oak trees (Wu et al. 2015. Diversity of great gray owl nest sites and nesting habitats in California. Journal of Wildlife Management).

I studied the movements and diet of the endemic Hawaiian thrush, ‘Ōma‘o (pictured), compared to the Warbling White-eye, a generalist-frugivore that may replace its ecological function in an invaded system. ‘Ōma‘o (50 g) are much larger than the Warbling White-eye (10 g) and are thus capable of dispersing larger native fruits than the White-eye. The White-eye, however, travels substantially farther and more frequently than the ‘Ōma‘o, meaning it is more likely to spread small seeds around. With the decline of large native frugivores, endemic and native bird-dispersed Hawaiian plants may see a decline in ability to perpetuate. Photo: Grigory Heaton/Flickr CC BY-NC 2.0. Wu et al. 2013. Movement Patterns of a Native and Non-native Frugivore in Hawaii and Implications for Seed Dispersal. Biotropica.