38 research outputs found
Comparison of Ichthyoplankton Sampling Conducted by the State of Alabama and the National Marine Fisheries Service During Southeast Area Monitoring and Assessment Program Fall Plankton Surveys
Data on the abundance and distribution of the early life stages of fishes were collected by the Alabama Department of Conservation and Natural Resources (ADCNR) and the National Marine Fisheries Service (NMFS) between 1984 and 2007 during Southeast Area Monitoring and Assessment Program (SEAMAP) cooperative resource surveys in the northern Gulf of Mexico. The ADCNR collected samples from various locations inside and outside Mobile Bay, while the NMFS collected samples farther offshore at four standard SEAMAP grid stations near the Alabama coast. We compared catch data on larval and juvenile fishes, along with environmental information, from a total of 225 neuston samples between the two sampling areas. Larval assemblages and diversity parameters varied between ADCNR and NMFS sampling sites, reflecting differences in environmental conditions. A less diverse assemblage dominated by estuarine taxa, including engraulids, sciaenids, gerreids, and clupeids, was found at ADCNR sampling locations, whereas a more diverse marine assemblage, including lutjanids, carangids, labrids, monacanthids, and scombrids, was observed at NMFS sampling sites. Larvae of red drum, Sciaenops ocellatus, an important federally managed species, were more prevalent at the ADCNR sampled sites than at the standard SEAMAP stations sampled by the NMFS near Mobile Bay. However, over the entire SEAMAP survey area, catch rates of red drum larvae at shallow (\u3c26 m) SEAMAP stations were comparable to, or even higher than, those observed at the ADCNR sites
The Role of Citizens in Detecting and Responding to a Rapid Marine Invasion
Documenting and responding to species invasions requires innovative strategies that account for ecological and societal complexities. We used the recent expansion of Indo-Pacific lionfish (Pterois volitans/miles) throughout northern Gulf of Mexico coastal waters to evaluate the role of stakeholders in documenting and responding to a rapid marine invasion. We coupled an online survey of spearfishers and citizen science monitoring programs with traditional fishery-independent data sources and found that citizen observations documented lionfish 1â2 years earlier and more frequently than traditional reef fish monitoring programs. Citizen observations first documented lionfish in 2010 followed by rapid expansion and proliferation in 2011 (+367%). From the survey of spearfishers, we determined that diving experience and personal observations of lionfish strongly influenced perceived impacts, and these perceptions were powerful predictors of support for initiatives. Our study demonstrates the value of engaging citizens for assessing and responding to large-scale and time-sensitive conservation problems
A field and video-annotation guide for baited remote underwater stereo-video surveys of demersal fish assemblages
Researchers TL, BG, JW, NB and JM were supported by the Marine Biodiversity Hub through funding from the Australian Government's National Environmental Science Program. Data validation scripts and GlobalArchive.org were supported by the Australian Research Data Commons, the Gorgon-Barrow Island Gorgon Barrow Island Net Conservation Benefits Fund, administered by the Government of Western Australia and the BHP/UWA Biodiversity and Societal Benefits of Restricted Access Areas collaboration.1. Baited remote underwater stereo-video systems (stereo-BRUVs) are a popular tool to sample demersal fish assemblages and gather data on their relative abundance and body-size structure in a robust, cost-effective, and non-invasive manner. Given the rapid uptake of the method, subtle differences have emerged in the way stereo-BRUVs are deployed and how the resulting imagery are annotated. These disparities limit the interoperability of datasets obtained across studies, preventing broad-scale insights into the dynamics of ecological systems. 2. We provide the first globally accepted guide for using stereo-BRUVs to survey demersal fish assemblages and associated benthic habitats. 3. Information on stereo-BRUV design, camera settings, field operations, and image annotation are outlined. Additionally, we provide links to protocols for data validation, archiving, and sharing. 4. Globally, the use of stereo-BRUVs is spreading rapidly. We provide a standardised protocol that will reduce methodological variation among researchers and encourage the use of Findable, Accessible, Interoperable, and Reproducible (FAIR) workflows to increase the ability to synthesise global datasets and answer a broad suite of ecological questions.Publisher PDFPeer reviewe
A cameraâbased method for estimating absolute density in animals displaying home range behaviour
1. The measurement of animal density may take advantage of recent technological achievements in wildlife video recording. Fostering the theoretical links between the patterns depicted by cameras and absolute density is required to exploit this potential. 2. We explore the applicability of the HutchinsonâWaserâs postulate (i.e. when animal density is stationary at a given temporal and spatial scale, the absolute density is given by the average number of animals counted per frame), which is a counterintuitive statement for most ecologists and managers who are concerned with counting the same individual more than once. We aimed to reconcile such scepticism for animals displaying home range behaviour. 3. The specific objectives of this paper are to generalize the HutchinsonâWaserâs postulate for animals displaying home range behaviour and to propose a Bayesian implementation to estimate density from counts per frame using video cameras. 4. Accuracy and precision of the method was evaluated by means of computer simulation experiments. Specifically, six animal archetypes displaying well-contrasted movement features were considered. The simulation results demonstrate that density could be accurately estimated after an affordable sampling effort (i.e. number of cameras and deployment time) for a great number of animals across taxa. 5. The proposed method may complement other conventional methods for estimating animal density. The major advantages are that identifying an animal at the individual level and precise knowledge on how animals move are not needed, and that density can be estimated in a single survey. The method can accommodate conventional camera trapping data. The major limitations are related to some implicit assumptions of the underlying model: the home range centres should be homogeneously distributed, the detection probability within the area surveyed by the camera should be known, and animals should move independently to one another. Further improvements for circumventing these limitations are discussed.Ministerio de EducaciĂłn, Cultura y Deporte, Grant/Award Number: FPU13/01440; Ministerio de EconomĂa y Competitividad Juan de la Cierva Postdoctoral Grant, Grant/Award Number: FJCI-2014-21 and CTM2015-69126-C2-1-R
A novel method to obtain accurate length estimates of carnivorous reef fishes from a single video camera
Environmental conditions and habitat characteristics influence trap and video detection probabilities for reef fish species
Observed and predicted number of priority fish species seen on video.
<p>Spatial predictions for the number of priority fish species on video were made at average values of all other predictor variables in the generalized additive model, and are shown from orange (indicating many species predicted) to blue (indicating low number of species predicted). Open circles show the mean observed number of species on video in 2011â2014 for each 0.25 Ă 0.25 degree cell.</p
Locations of video samples included in the analyses from the Southeast Reef Fish Survey.
<p>Data is from the southeast United States, 2011â2014 (gray points; <i>N</i> = 4,855 videos in total). Note that points often overlap. Gray isobaths indicate 30-, 50-, and 100-m depths, and arrows indicate the general path of the Gulf Stream.</p
Locations of selected uncommon reef fish species seen on videos.
<p>Note that some points overlap. Gray isobaths indicate 30-, 50-, and 100-m depths.</p
Spatial Distribution of Reef Fish Species along the Southeast US Atlantic Coast Inferred from Underwater Video Survey Data
<div><p>Marine fish abundance and distribution often varies across spatial scales for a variety of reasons, and this variability has significant ecological and management consequences. We quantified the distribution of reef-associated fish species along the southeast United States Atlantic coast using underwater video survey samples (<i>N</i> = 4,855 in 2011â2014) to elucidate variability within species across space, depths, and habitats, as well as describe broad-scale patterns in species richness. Thirty-two species were seen at least 10 times on video, and the most commonly observed species were red porgy (<i>Pagrus pagrus</i>; 41.4% of videos), gray triggerfish (<i>Balistes capriscus</i>; 31.0%), black sea bass (<i>Centropristis striata</i>; 29.1%), vermilion snapper (<i>Rhomboplites aurorubens</i>; 27.7%), and red snapper (<i>Lutjanus campechanus</i>; 22.6%). Using generalized additive models, we found that most species were non-randomly distributed across space, depths, and habitats. Most rare species were observed along the continental shelf break, except for goliath grouper (<i>Epinephelus itajara</i>), which was found on the continental shelf in Florida and Georgia. We also observed higher numbers of species in shelf-break habitats from southern North Carolina to Georgia, and fewer in shallower water and at the northern and southern ends of the southeast United States Atlantic coast. Our study provides the first broad-scale description of the spatial distribution of reef fish in the region to be based on fishery-independent data, reinforces the utility of underwater video to survey reef fish, and can help improve the management of reef fish in the SEUS, for example, by improving indices of abundance.</p></div