Robert Ahrens
YOU?
Author Swipe
View article: Oyster cultch–recruit patterns provide new insight into the restoration and management of a critical resource
Oyster cultch–recruit patterns provide new insight into the restoration and management of a critical resource Open
Objective Our objective was to quantify the relationship between oyster cultch mass (kg/m³) and density (oysters/m²) of live eastern oyster Crassostrea virginica on intertidal reefs in Suwannee Sound, Florida. We also evaluated the potenti…
View article: Process and sampling variance within fisheries stock assessment models: estimability, likelihood choice, and the consequences of incorrect specification
Process and sampling variance within fisheries stock assessment models: estimability, likelihood choice, and the consequences of incorrect specification Open
Increasingly, mixed-effect fishery stock assessment models are being developed where deviations about functional forms of different processes are modelled as random effects and the extent of variance is estimated internal to the model. Con…
View article: Boxing as a Therapeutic Intervention for Youth With Autism Spectrum Disorder: A Preliminary Study
Boxing as a Therapeutic Intervention for Youth With Autism Spectrum Disorder: A Preliminary Study Open
Date Presented 04/21/2023 We describe preliminary data from an exploratory study on the potential effects of boxing as a therapeutic intervention for youth with autism spectrum disorder (ASD). Primary Author and Speaker: Razan Hamed Contri…
View article: When to conduct, and when not to conduct, management strategy evaluations
When to conduct, and when not to conduct, management strategy evaluations Open
The basis of natural resource management is decision making under uncertainty while balancing competing objectives. Within fisheries management, a process described as management strategy evaluation (MSE) is becoming increasingly requested…
View article: Correction to: Cascading effects of climate change on recreational marine flats fishes and fisheries
Correction to: Cascading effects of climate change on recreational marine flats fishes and fisheries Open
View article: Cascading effects of climate change on recreational marine flats fishes and fisheries
Cascading effects of climate change on recreational marine flats fishes and fisheries Open
View article: Functional and phylogenetic diversity of sharks in the Northeastern Pacific
Functional and phylogenetic diversity of sharks in the Northeastern Pacific Open
Aim The expansive spatial scale of pelagic communities and the difficulty in acquiring pelagic species' functional traits have stymied an understanding of marine community dynamics. We assembled and analysed a shark trait database and comm…
View article: Note of appreciation
Note of appreciation Open
View article: A multidisciplinary approach to estimating red snapper, Lutjanus campechanus, behavioral response to mobile camera and sonar sampling gears
A multidisciplinary approach to estimating red snapper, Lutjanus campechanus, behavioral response to mobile camera and sonar sampling gears Open
View article: Fish Population Recruitment 2: Stock Recruit Relationships and why they matter for stock assessment
Fish Population Recruitment 2: Stock Recruit Relationships and why they matter for stock assessment Open
A good understanding of stock recruitment is essential for accurate stock assessment and good fisheries management. But recruitment and how it is used can be difficult to understand. This publication uses a recent Florida spotted seatrout …
View article: Assessing likelihoods for fitting composition data within stock assessments, with emphasis on different degrees of process and observation error
Assessing likelihoods for fitting composition data within stock assessments, with emphasis on different degrees of process and observation error Open
Fisheries stock assessments have traditionally modeled age and size composition data using the multinomial likelihood, however the multinomial cannot appropriately account for the correlations and overdispersion that exist in the observed …
View article: Poaching is directly and indirectly driving the decline of South Africa's large population of white rhinos
Poaching is directly and indirectly driving the decline of South Africa's large population of white rhinos Open
Large herbivores, particularly in water limited systems, are vulnerable to the impacts of poaching (illegal hunting) and human‐induced climate changes. However, we have little understanding of how these processes can reshape their populati…
View article: Age and Growth of Yellowfin Tuna in the U.S. Gulf of Mexico and Western Atlantic
Age and Growth of Yellowfin Tuna in the U.S. Gulf of Mexico and Western Atlantic Open
Age, growth, and mortality were estimated for Yellowfin Tuna Thunnus albacares from the U.S. Gulf of Mexico and western Atlantic Ocean. During 2004–2017, 3,443 Yellowfin Tuna were sampled, primarily from recreational landings off the coast…
View article: Ensemble Random Forests as a tool for modeling rare occurrences
Ensemble Random Forests as a tool for modeling rare occurrences Open
Relative to target species, priority conservation species occur rarely in fishery interactions, resulting in imbalanced, overdispersed data. We present Ensemble Random Forests (ERFs) as an intuitive extension of the Random Forest algorithm…
View article: Testing the efficacy of lionfish traps in the northern Gulf of Mexico
Testing the efficacy of lionfish traps in the northern Gulf of Mexico Open
Spearfishing is currently the primary approach for removing invasive Indo-Pacific lionfish (Pterois volitans/miles complex) to mitigate their impacts to western Atlantic marine ecosystems. However, a substantial portion of lionfish spawnin…
View article: Precipitous Declines in Northern Gulf of Mexico Invasive Lionfish Populations Following the Emergence of an Ulcerative Skin Disease
Precipitous Declines in Northern Gulf of Mexico Invasive Lionfish Populations Following the Emergence of an Ulcerative Skin Disease Open
View article: Saving large fish through harvest slots outperforms the classical minimum‐length limit when the aim is to achieve multiple harvest and catch‐related fisheries objectives
Saving large fish through harvest slots outperforms the classical minimum‐length limit when the aim is to achieve multiple harvest and catch‐related fisheries objectives Open
We address the problem of optimal size‐selective exploitation in an age‐structured fish population model by systematically examining how density and size dependency in growth, mortality and fecundity affect optimal harvesting patterns when…
View article: Resilience Management for Conservation of Inland Recreational Fisheries
Resilience Management for Conservation of Inland Recreational Fisheries Open
Resilience thinking has generated much interest among scientific communities, yet most resilience concepts have not materialized into management applications. We believe that using resilience concepts to characterize systems and the social…
View article: Saving large fish through harvest slots outperforms the classical minimum-length limit when the aim is to achieve multiple harvest and catch-related fisheries objectives
Saving large fish through harvest slots outperforms the classical minimum-length limit when the aim is to achieve multiple harvest and catch-related fisheries objectives Open
We address the problem of optimal size-selective exploitation in an age-structured fish population model by systematically examining how density- and size-dependency in growth, mortality and fecundity affect optimal harvesting patterns whe…
View article: Identifying forage populations of concern: A new perspective based on predator recruitment considerations
Identifying forage populations of concern: A new perspective based on predator recruitment considerations Open
Concerns about forage fish taxa declines caused by fishing or environmental change and their impact on predator populations have become an important issue in fisheries management. However, it has proven difficult to identify critical forag…
View article: Evolutionary and demographic impacts of sex change rules and size-selective exploitation on sequential hermaphrodites
Evolutionary and demographic impacts of sex change rules and size-selective exploitation on sequential hermaphrodites Open
Relatively few studies have addressed fishery-induced-evolution of sequential hermaphrodites although declines in the mean size-at-maturation and/or sex change have been documented for several species. We sought to explore the evolutionary…
View article: Estimating site-specific spawning parameters for a spawning aggregation: an example with spotted seatrout
Estimating site-specific spawning parameters for a spawning aggregation: an example with spotted seatrout Open
MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 624:117-129 (2019) - DOI: https://doi.org/10…
View article: An Ecosystem-Based Approach to Evaluating Impacts and Management of Invasive Lionfish
An Ecosystem-Based Approach to Evaluating Impacts and Management of Invasive Lionfish Open
Species invasions in marine ecosystems pose a threat to native fish communities and can disrupt the food webs that support valuable commercial and recreational fisheries. In the Gulf of Mexico, densities of invasive Indo-Pacific Lionfish, …
View article: Effects of biological, economic and management factors on tuna and billfish stock status
Effects of biological, economic and management factors on tuna and billfish stock status Open
Commercial tunas and billfishes (swordfish, marlins and sailfish) provide considerable catches and income in both developed and developing countries. These stocks vary in status from lightly exploited to rebuilding to severely depleted. Pr…
View article: Comparison of growth models for sequential hermaphrodites by considering multi-phasic growth
Comparison of growth models for sequential hermaphrodites by considering multi-phasic growth Open
View article: Elasmobranch bycatch associated with the shrimp trawl fishery off the Pacific coast of Costa Rica, Central America
Elasmobranch bycatch associated with the shrimp trawl fishery off the Pacific coast of Costa Rica, Central America Open
Demersal sharks and rays are common yet vulnerable components of the bycatch in tropical bottom-trawl fisheries. Little is known about the elasmobranch assemblages associated with most of these fisheries, particularly within the eastern tr…
View article: Combining Samples from Multiple Gears Helps to Avoid Fishy Growth Curves
Combining Samples from Multiple Gears Helps to Avoid Fishy Growth Curves Open
Size-at-age information is critical in estimating growth parameters (e.g., the von Bertalanffy growth function [VBGF]) that are used to assess fish populations. Due to gear selectivity, single sampling methods rarely sample all ages or all…
View article: Elasmobranch bycatch associated with the shrimp trawl fishery off the Pacific coast of Costa Rica, Central America
Elasmobranch bycatch associated with the shrimp trawl fishery off the Pacific coast of Costa Rica, Central America Open
View article: The curious case of eastern oyster Crassostrea virginica stock status in Apalachicola Bay, Florida
The curious case of eastern oyster Crassostrea virginica stock status in Apalachicola Bay, Florida Open
The Apalachicola Bay, Florida, eastern oyster ( Crassostrea virginica ) industry has annually produced about 10% of the U.S. oyster harvest. Today’s simple individual-operator, hand-tonging, small-vessel fishery is remarkably similar to th…