Publications

The National Park Service (NPS) manages the Nation’s most iconic destinations that attract millions of visitors from across the Nation and around the world. Trip-related spending by NPS visitors generates and supports economic activity within park gateway communities. This report summarizes the annual economic contribution analysis that measures how NPS visitor spending cycles through...

Snake Creek flows east from the southern Snake Range in Nevada over complex lithology before leaving Great Basin National Park. The river travels over a section of karst limestone where some surface water naturally recharges the groundwater flow system. In 1961 a water diversion pipeline was constructed by downstream water users to transport surface water through the groundwater recharge...

Common assumptions about how vegetation affects wetland methane (CH) flux include acting as conduits for CH release, providing carbon substrates for growth and activity of methanogenic organisms, and supplying oxygen to support CH oxidation. However, these effects may change through time, especially in seasonal wetlands that experience drying and re-wetting, or change across space...

A comprehensive understanding of fish populations and their interactions is the cornerstone of modern fishery management and the basis for Fish Community Goals and Objectives for Lake Erie (Ryan et al. 2003). This report is responsive to U.S. Geological Survey (USGS) obligations via Memorandum of Understanding (MOU) with the Great Lakes Council of Lake Committees (CLC) to provide...

No abstract available.

Glaciers are a key indicator of changing climate in the high mountain landscape. Glacier variations across a mountain range are ultimately driven by regional climate forcing. However, changes also reflect local, topographically driven processes such as snow avalanching, snow wind-drifting, and radiation shading as well as the initial glacier conditions such as hypsometry and ice...

In highly mobile philopatric species, defining the scale of natal homing is fundamental to characterizing population dynamics and effectively managing distinct populations. Genetic tools have provided evidence of regional natal philopatry in marine turtles, but extensive sharing of maternally inherited mitochondrial control region (CR) haplotypes within regions (

Understanding trends in abundance is important to fisheries conservation, but techniques for estimating streamwide abundance of cryptic fishes with strong habitat–abundance relationships are not well established and need further development. We developed techniques for addressing this need using the Harlequin Darter Etheostoma histrio, a small, cryptic freshwater fish associated with...

Advances in video technology enable new strategies for stream fish research. We compared juvenile (age‐0) and adult (age 1+) Brook Trout Salvelinus fontinalis abundance estimates from underwater video with backpack electrofishing and dive‐count methods across a series of stream pools in Shenandoah National Park, Virginia (n = 41). Video methods estimated greater mean abundance of adult...

Various vector control options are increasingly being considered to safeguard forest birds in their natural habitats from avian malaria transmission. However, vector control options require localized deployment that is not logistically, ethically, ecologically, nor economically viable everywhere and all the time. Based on thermal tolerances of the sporogonic stages of avian malaria...

Dam operations can affect mixing of the water column, thereby influencing thermal heterogeneity spatially and temporally. This occurs by restricting or eliminating connectivity in longitudinal, lateral, vertical, and temporal dimensions. We examined thermal heterogeneity across space and time and identified potential cold-water refuges for salmonids in a large impounded river in inland

We report discovery of an established population of the Asian swamp eel Amphipnous cuchia (Hamilton, 1822) in Bayou St. John, an urban waterway in New Orleans, Louisiana, USA. This fish, commonly referred to as cuchia (kuchia), is a member of the family Synbranchidae and is native to southern and southeastern Asia. Recently-used synonyms include Monopterus cuchia and Ophichthys cuchia...