Assistant Professor of Biology
Dale teaches biology, ecology, natural resources management, ornithology, winter ecology and environmental science. He works with Northwestern students to study the reuse of woodpecker cavities by secondary cavities users on the forested portions of the Northwestern Campus. He is married and has one daughter. Personal interests include cycling, Nordic skiing, and bird watching.
“The God who in Himself is invisible and unknowable has made Himself both visible and knowable through what he has made. The creation is a visible disclosure of the invisible God, an intelligible disclosure of the otherwise unknown God. Just as artists reveal themselves in what they draw, paint and sculpt, so the Divine Artist has revealed Himself in His creation.” -John Stott
Courses I Teach:
Principals of Biology III -- Freshman survey course introducing students to major concepts of the life sciences with an emphasis in botany, creation and evolution, and ecology. Topics include basic ecological principle such as the role of natural and sexual selection, discussion on the different theories on the origins of species in the context of a Christian worldview, and an introduction of plant structure and function, human impact on biodiversity, and Christian environmental stewardship.
Ecology -- This course will review major ecological concepts, identify the techniques used by ecologists, and provide an overview of local and global environmental issues and the role of Christian stewardship of creation.
Natural Resources Management -- An advanced survey of the distribution and management of natural resources with special emphasis on developing critical thinking skills and new solutions to problems of resource scarcity. Topics include: wildlife and wild-lands, energy, water, air, and food. Economics, demographic, religious and political issues are considered as they affect resources.
Winter Ecology -- Emphasizes the effects of winter abiotic conditions on organisms and subsequent organismal adaptations to these conditions. Energy flux, snowpack physics, plant and animal adaptations, and the influence of winter on wildlife management are emphasized through lectures and field laboratories.
Ornithology -- This course examines the biology, ecology, diversity, behavior, and field identification of birds. Special attention is paid to local species of the upper Midwest.
Environmental Science -- A course for non-majors focusing on the interrelationships between organisms and their environment and how humans manage those communities. Topics include biodiversity, air and water pollution, waste disposal, population growth, resource management, public policy, ethics and Christian stewardship of God's creation.
The University of Northwestern campus is the perfect location to study the influence of urbanization on biodiversity. My students and I study the flora and fauna of our campus from numerous perspectives. My ongoing project examines woodpecker cavities and the community of secondary cavity users (animals that use cavities but can not excavate their own). We utilize the managed parklands next to beautiful Lake Johanna as well as the minimally managed forest along Little Lake Johanna.
Gentry, D. J., and K. T. Vierling. 2008. Reuse of woodpecker cavities in the breeding and non-breeding seasons in old burn habitats in the Black Hills, South Dakota. American Midland Naturalist 160:413-429
Vierling, K. T., and D. J. Gentry. 2009. Red-headed Woodpecker density and productivity in relation to time since fire in burned pine forests. Fire Ecology 4:15-25.
Vierling, K. T., D. J. Gentry, and A. Haines. 2009. Nest niche partitioning of Lewis’s and Red-headed Woodpeckers in burned pine forests. The Wilson Journal of Ornithology 121:89-96.
Gentry, D. J., and K. T. Vierling. 2007. Old burns as source habitats for Lewis’s Woodpeckers breeding in the Black Hills of South Dakota. The Condor 109:122-131.
Gentry, D. J., D. L. Swanson, and J. D. Carlisle. 2006. Species richness and nesting success of songbirds in natural river corridors and anthropogenic woodlands in southeastern South Dakota. The Condor 108:140-153.