Fisheries Management & Conservation Flashcards

Which habitat characteristic is MOST critical for the successful spawning of brook trout in headwater streams?

Answer: Upwelling of cold, well-oxygenated groundwater through clean gravel substrate

Brook trout require clean gravel redds with upwelling groundwater that delivers oxygen directly to eggs and removes metabolic waste products.

An adaptive management framework in fisheries requires which of the following as its foundational step?

Answer: Formulating explicit hypotheses and management objectives before intervention

Adaptive management requires clearly stated objectives and explicit hypotheses about system responses before implementing management actions, so outcomes can be compared against predictions.

What is the primary purpose of a 'slot limit' regulation in recreational fisheries management?

Answer: Protect both sub-adult fish below and large trophy fish above a specified size range

Slot limits protect fish below the minimum slot size (allowing growth to maturity) and above the maximum slot size (protecting trophy individuals and highly fecund adults).

The concept of 'trophic cascade' was first convincingly demonstrated in freshwater systems through experiments involving the removal of which predator?

Answer: Largemouth bass from small lakes

Stephen Carpenter and James Kitchell's whole-lake experiments demonstrated that removing largemouth bass triggered cascading effects on zooplankton and phytoplankton through meso-predator release.

Which technique is used to assess fish habitat quality by measuring the proportion of stream substrate composed of fine sediment (<2 mm) embedded in gravel?

Answer: Embeddedness assessment

Embeddedness assessment quantifies the degree to which gravel and cobble are surrounded or covered by fine sediment, which reduces interstitial space critical for fish spawning and invertebrate habitat.

In the context of marine protected areas (MPAs), a 'no-take zone' differs from a 'no-entry zone' in that:

Answer: No-take zones allow diving and non-extractive recreation; no-entry zones prohibit all human presence

No-take zones prohibit all extractive activities (fishing, collecting) but may allow non-extractive uses like diving, while no-entry zones restrict all human access.

Which statistical method is most appropriate for estimating fish abundance from mark-recapture data when the assumptions of closed population, equal catchability, and no marks lost are met?

Answer: Lincoln-Petersen estimator

The Lincoln-Petersen estimator is the classic two-sample mark-recapture method for closed populations meeting assumptions of equal catchability and permanent marks.