Abstract Fishery collapses cause substantial economic and ecological harm, but common management actions often fail to prevent overfishing. Minimum length limits are perhaps the most fishing regulation used in both commercial recreational fisheries, their conservation benefits can be influenced by discard mortality of fish caught released below legal length. We constructed a computer model evaluate how could influence utility minimum regulations. evaluated policy performance across two...

Abstract The practice of catch and release (CR) as a fisheries management tool to reduce fishing mortality is widely applied in both freshwater marine fisheries, whether from shifts angler attitudes related harvest or the increasing use restrictions such closed seasons length limits. This approach assumes that for CR policies benefit stock, will result much lower than would otherwise occur. There are many challenges design studies assess mortality, practical settings it difficult obtain...

Information characterising site fidelity and abundance for common bottlenose dolphins (Tursiops truncatus) along the southwest coast of Florida is important defining stock structure management purposes. Long-term ranging patterns in Charlotte Harbor Pine Island Sound, were investigated using photo-ID data collected during 566 boat-based surveys from 1982 through 2007. Seasonal estimates generated seven multi-week field seasons 2001 2006, before after a major hurricane red tide event occurred...

The most controversial fishery in U.S. waters of the Gulf Mexico (Gulf) is for northern red snapper Lutjanus campechanus, which collapsed late 1980s when stock biomass became too low to be fished commercially eastern Gulf. Red management began 1989; now showing signs recovery. Fishery Management Council has been slow sufficiently reduce catches directed fisheries rebuild a timely fashion, although compliance with Magnuson-Stevens Reauthorization Act 2006 (MSRA) required substantial cuts...

Camp, E. V., W. Pine III, K. Havens, A. S. Kane, C. J. Walters, T. Irani, B. Lindsey, and G. Morris. 2015. Collapse of a historic oyster fishery: diagnosing causes identifying paths toward increased resilience. Ecology Society 20(3):45. https://doi.org/10.5751/ES-07821-200345

Oyster reefs are among the world's most endangered marine habitats with an estimated 85% loss from historical levels worldwide. offer diverse ecological and social services for people natural environments; unfortunately, also highly sensitive to impairment human-induced disasters. Understanding resilience of oyster reef communities disturbance is key developing effective conservation restoration plans. Florida's Big Bend coastline (Gulf Mexico coast Crystal River Apalachee Bay) supports...

Abstract The federally endangered humpback chub Gila cypha in the Colorado River within Grand Canyon is currently focus of a multiyear program ecosystem‐level experimentation designed to improve native fish survival and promote population recovery as part Glen Dam Adaptive Management Program. A key element this experiment was 4‐year effort remove nonnative fishes from critical habitat, thereby reducing potentially negative interactions between fishes. Over 36,500 15 species were captured...

ABSTRACT Floodplain habitats provide critical spawning and rearing for many large‐river fishes. The paradigm that floodplains are essential is often a key reason restoring altered rivers to natural flow regimes. However, few studies have documented spatial temporal utilization of floodplain by adult fish sport or commercial management interest assessed obligatory access species' persistence. In this study, we applied telemetry techniques examine movements between mainstem habitats, paired...

Pine, W. E., III, C. J. Walters, E. V. Camp, R. Bouchillon, Ahrens, L. Sturmer, and M. Berrigan, 2015. The curious case of eastern oyster Crassostrea virginica stock status in Apalachicola Bay, Florida. Ecology Society 20(3):46. https://doi.org/10.5751/ES-07827-200346

Abstract Monitoring trends in the occurrence of species over time is important for informing conservation plans and concurrent management actions. Understanding effectiveness field methodologies collecting accurate precise data crucial optimizing allocation sampling effort resources. In this study, we compared mammalian richness detection probabilities between three methodologies: line transects, ground camera traps arboreal Nyungwe National Park, Rwanda. Arboreal may be suitable monitoring...

Abstract Observed ecosystem responses to fisheries management experiments have often been either much smaller or in the opposite direction of expected based on experience population models. Examples these can be found even for some very simple experimental manipulations such as predator and prey small lakes ponds fish harvest closures. Such counter-intuitive prediction failures offer opportunities identify key processes variables that are not widely considered models used evaluate...

The Suwannee River, Florida, population of the Gulf Mexico sturgeon Acipenser oxyrinchus desotoi, a subspecies Atlantic A. oxyrinchus, was evaluated using capture–recapture approach and an age-structured model to examine trends from 1986 through 1995. analysis revealed positive rate change (λ) in adult population, indicating that it slowly increasing mid-1980s mid-1990s. highly sensitive changes egg-to-age-1 mortality, percentage females spawn annually, mortality. predicted even slight...

We used a simulation model to evaluate how recruitment variability and evaluation duration would affect fisheries managers' ability detect fish population responses minimum length limit. Length limits modeled were 254 mm for white crappie Pomoxis annularis 305, 356, 457 largemouth bass Micropterus salmoides. Simulations conducted at variation (coefficient of variation, CV = 100 × SD/mean) 20–100% age-1 recruits. evaluated density, biomass, total catch (fish harvested released), yield,...

Abstract The abundance of the Little Colorado River population federally listed humpback chub Gila cypha in Grand Canyon has been monitored since late 1980s by means catch rate indices and capture–recapture‐based estimators. Analyses data from all sources using various methods are consistent indicate that adult declined monitoring began. Intensive tagging led to a high proportion (>80%) being marked mid‐1990s. Analysis these both closed open estimation models yields results agree with...

Abstract The flathead catfish Pylodictis olivaris , a carnivorous fish species native to most of the central interior basin North America, has been introduced into at least 13 U.S. states and 1 Canadian province. Concurrent declines in abundance fishes have reported aquatic systems where introduced. To evaluate potential impact this invasive on community we developed an ecosystem simulation model (including catfish) based empirical data collected from Carolina coastal river. results suggest...

Age-structured models are widely used in fisheries stock assessments and contain two very important parameters that determine the rate amount of harvest can be safely taken: compensation juvenile survival (κ) unfished biomass (B o ). These often confounded. It is common for relative abundance indices to lack contrast, use informative priors, or fixing at least one these parameters, necessary develop management advice. Providing advice proceeds by transforming estimates biological variables...

Abstract Riverine ecosystems have been altered in many large catchments by dam development to provide water, power, flood control and navigational benefits humans. Conservation actions these river are commonly focused on minimum releases of water downstream ecosystems. Increasingly release approaches being replaced with ‘experimental’ flows that mimic natural conditions order benefit riverine While new policies intuitive their design, there is limited data how actually respond more flows. A...

Black crappies Pomoxis nigromaculatus exhibit highly variable survival to adulthood because of their varying larval and juvenile abundance, growth, mortality during early life. We examined how growth changed with hatch date, prey density, water temperature for 7-d cohorts black in Lake Wauberg, Florida (a 150-ha hypereutrophic natural lake) spring summer 1998. Fish were collected once per week from March through June twice month July August by means an otter trawl. Based on daily otolith...

Abstract In two coastal North Carolina rivers (Contentnea Creek and the Northeast Cape Fear River), we found food habits of introduced flathead catfish Pylodictis olivaris to be primarily piscivorous, which could restructure or suppress native fish communities through direct predation. Fish crayfish contributed more than 50% stomach contents by percent occurrence, number, weight in both during each 2 years. Significant differences diet composition (percent number) were between years River...

Abstract Rapid human population growth and an associated increase in consumptive water demands within the ecologically diverse Apalachicola–Chattahoochee–Flint (ACF) River basin of southeastern United States have led to a series highly publicized wars, exacerbated by recent drought conditions, between states Alabama, Georgia, Florida. A key issue is how managing riverine flows meet needs will affect viability species that are federally listed as threatened or endangered, including Gulf...

Abstract Catfishes (Siluriformes: Pimelodidae) in the Amazon River Basin serve important ecological and economic roles structuring foodwebs, transferring nutrients providing food resources for human populations. Large‐scale developments such as construction of Interoceanic Highway associated proposed hydroelectric facilities could lead to alterations river hydrology aquatic ecosystems within headwater regions. We assessed temporal spatial distribution patterns catfish larvae determine...

We developed a geochemical atlas of the Colorado River in Grand Canyon and its tributary, Little River, used it to identify provenance habitat use by Federally Endangered humpback chub, Gila cypha. Carbon stable isotope ratios (δ(13)C) discriminate best between two rivers, but fine scale analysis otoliths requires rare, expensive instrumentation. therefore correlated other tracers (SrSr, Ba, Se ratio Ca) δ(13)C that are easier quantify with microchemical techniques. Although River's water...

Abstract Many management actions in aquatic ecosystems are directed at restoring or improving specific habitats to benefit fish populations. In the Grand Canyon reach of Colorado River, experimental flow operations as part Glen Dam Adaptive Management Program have been designed restore sandbars and associated backwater habitats. Backwaters can warmer water temperatures than other habitats, native fish, including federally endangered humpback chub Gila cypha , frequently observed backwaters,...