Outdoor recreation experiences at Diamond Lake, Oregon (USA), before, during and after a biological disruption.

This chapter examines recreational displacement in response to a unique management and biological event: the introduction of the non-native cyprinid tui chub (Gila bicolor pectinifer) into Diamond Lake. The study demonstrates the behavioural reactions of visitors in response to a management action or a 'controlled' decision to intervene in the impacts of the invasive tui chub. About half of the Diamond Lake visitors who still visit the lake exhibited some temporal and/or spatial displacement behaviours. Visitors at Diamond Lake dealt with the lake's closure by remaining at the lake but participating in another activity (activity substitution) or by moving to an alternative location to continue their primary activity (spatial displacement/resource substitution). More than one-third of all Diamond Lake visitors chose not to recreate during that period (temporal displacement) and 17% changed both their activity and location (absolute displacement).

Outdoor recreation experiences at Diamond Lake, Oregon (USA), before, during and after a biological disruption.

This chapter examines recreational displacement in response to a unique management and biological event: the introduction of the non-native cyprinid tui chub (Gila bicolor pectinifer) into Diamond Lake. The study demonstrates the behavioural reactions of visitors in response to a management action or a 'controlled' decision to intervene in the impacts of the invasive tui chub. About half of the Diamond Lake visitors who still visit the lake exhibited some temporal and/or spatial displacement behaviours. Visitors at Diamond Lake dealt with the lake's closure by remaining at the lake but participating in another activity (activity substitution) or by moving to an alternative location to continue their primary activity (spatial displacement/resource substitution). More than one-third of all Diamond Lake visitors chose not to recreate during that period (temporal displacement) and 17% changed both their activity and location (absolute displacement).

Mass Harvesting, Ichthyofaunal Assemblages, and Ancestral Paiute Fishing in the North American Great Basin

Documenting variability in the archaeological record is critical to our understanding human fishing adaptations in the North American Great Basin over time. Unfortunately, in the absence of robust middle range techniques for interpreting fishbone assemblages, many studies have been limited in their capacity to engage in theoretical discussions of the role of fishing in forager subsistence regimes. The Northern Paiute in Oregon and Nevada exploited seasonally aggregated tui chub (Siphateles bicolor) through mass-harvesting techniques using nets and baskets. This article integrates experimental studies with ethnographic and archaeological data to infer the types of fishing gear that were used from the reconstructed sizes of tui chub remains. The mean size of fish assemblages is compared to the coefficient of variation to identify fishing techniques based on the size parameters of gear types, and a technology investment model is used to assess regional variations in commitments to fishing in open lake and marshland settings. Results are compared to tui chub assemblages from two protohistoric archaeological sites in eastern Oregon, revealing two distinctive fishing strategies with general implications for the organization of labor by hunter-gatherer fisherfolk.

Response to Comments for “An Ecological Function Approach to Managing Harmful Cyanobacteria in Three Oregon Lakes: Beyond Water Quality Advisories and Total Maximum Daily Loads (TMDLs)”, Water 2019, 11, 1125

The commenter’s key argument is that Diamond Lake’s problem is strictly one of biomass, i.e., introduction of the invasive Tui Chub fish. There are a few things to note in that respect. The Tui Chub is a bait fish. It is a lower-order prey fish for higher-order trout/salmonid species. Tui Chub is zooplanktivorous. Since the Tui Chub feed on zooplankton, if they themselves are prey for other species (or are being “culled” by artificial means), and there is no other entity to feed on the plankton and algae, the result would be a mass of plankton/algae bloom (i.e., harmful algal blooms (HABs)). This would lead to anoxic conditions in the euphotic zone, which puts even more stress on the higher-order trout/salmonid species. Our work found that the biological community (i.e., invertebrates and fish) are lagging indicators (i.e., response indicators).