Geology topics

Brian S. Harmon

Publications and source records attributed to Brian S. Harmon.

3 recordsLinked to original sources

USGS2018

Variation in angler distribution and catch rates of stocked rainbow trout in a small reservoir

We investigated the spatial and temporal relationship of catch rates and angler party location for two days following a publicly announced put-and-take stocking of rainbow trout ( Oncorhynchus mykiss ). Catch rates declined with time since stocking and distance from stocking. We hypothesized that opportunity for high catch rates would cause anglers to fish near the stocking location and disperse with time, however distance between angler parties and stocking was highly variable at any given time. Spatially explicit differences in catch rates can affect fishing quality. Further research could investigate the variation between angler distribution and fish distribution within a waterbody.

PLoS ONE↗

USGS2017

Estimating the number of recreational anglers for a given waterbody

Knowing how many anglers use a given body of water is paramount for understanding components of a fishery related to angling pressure and harvest, yet no study has attempted to provide an estimate of the population size of anglers for a given waterbody. Here, we use information from creel surveys in a removal-sampling framework to estimate total numbers of anglers using six reservoirs in Nebraska, USA, and we examine the influence of the duration of sampling period on those estimates. Population estimates (N ± SE) of unique anglers were 2050 ± 45 for Branched Oak Lake, 1992 ± 29 for Calamus Reservoir, 929 ± 10 for Harlan County Reservoir, 985 ± 24 for Lake McConaughy, 1277 ± 24 for Merritt Reservoir, and 916 ± 18 for Pawnee Lake during April–October 2015. Shortening the sampling period by one or more months generally resulted in a greater effect on estimates of precision than on estimates of overall abundance. No relationship existed between abundances of unique anglers and angling pressures across reservoirs and sampling duration, indicative of a decoupling of angler abundance and angling pressure. The approach outlined herein has potential to provide defendable answers to “how many are there?”, questions we ask when subjects cannot be marked, which should provide new insights about angler populations and subpopulations.

Nebraska↗

USGS2016

Fishing for ecosystem services

Ecosystems are commonly exploited and manipulated to maximize certain human benefits. Such changes can degrade systems, leading to cascading negative effects that may be initially undetected, yet ultimately result in a reduction, or complete loss, of certain valuable ecosystem services. Ecosystem-based management is intended to maintain ecosystem quality and minimize the risk of irreversible change to natural assemblages of species and to ecosystem processes while obtaining and maintaining long-term socioeconomic benefits. We discuss policy decisions in fishery management related to commonly manipulated environments with a focus on influences to ecosystem services. By focusing on broader scales, managing for ecosystem services, and taking a more proactive approach, we expect sustainable, quality fisheries that are resilient to future disturbances. To that end, we contend that: (1) management always involves tradeoffs; (2) explicit management of fisheries for ecosystem services could facilitate a transition from reactive to proactive management; and (3) adaptive co-management is a process that could enhance management for ecosystem services. We propose adaptive co-management with an ecosystem service framework where actions are implemented within ecosystem boundaries, rather than political boundaries, through strong interjurisdictional relationships.

Journal of Environmental Management↗