Search

Your search keyword '"Merten, Wessley"' showing total 20 results
Start Over Author "Merten, Wessley"
20 results on '"Merten, Wessley"'

1. Spatiotemporal dynamics of dolphinfish (Coryphaena hippurus) in the western Atlantic Ocean

Author

Damiano, Matthew D., Merten, Wessley, Karnauskas, Mandy, and Cao, Jie

Subjects
United States. South Atlantic Fishery Management Council, Population biology, Ocean, Zoology and wildlife conservation
Abstract

The dolphinfish (Coryphaena hippurus) is a mid-level trophic predator and migratory, cosmopolitan species of pelagic fish that is found throughout tropical and subtropical regions (Palko et al., 1982; Luckhurst, 2017; [...]

Published
2024
Full Text
View/download PDF

3. Global Fishing Watch: Bringing Transparency to Global Commercial Fisheries

Author

Merten, Wessley, Reyer, Adam, Savitz, Jackie, Amos, John, Woods, Paul, and Sullivan, Brian

Subjects
Computer Science - Computers and Society
Abstract

Across all major industrial fishing sectors, overfishing due to overcapacity and lack of compliance in fishery governance has led to a decline in biomass of many global fish stocks. Overfishing threatens ocean biodiversity, global food security, and the livelihoods of law abiding fishermen. To address this issue, Global Fishing Watch (GFW) was created to bring transparency to global fisheries using computer science and big data analytics. A product of a partnership between Oceana, SkyTruth and Google, GFW uses the Automatic Identification System, or AIS, to analyze the movement of vessels at sea. AIS provides vessel location data, and GFW uses this information to track global vessel movement and apply algorithms to classify vessel behavior as "fishing" or "non-fishing" activity. Now publicly available, anyone with an internet connection can monitor when and where trackable commercial fishing appears to be occurring around the world. Hundreds of millions of people around the world depend on our ocean for their livelihoods, and many more rely on it for food. Collectively, the various applications of GFW will help reduce overfishing and illegal fishing, restore the ocean's abundance, and ensure sustainability through better monitoring and governance of our marine resources., Comment: Presented at the Data For Good Exchange 2016

Published
2016

7. Genetic structure and dispersal capabilities of dolphinfish (Coryphaena hippurus) in the western central Atlantic

Author

Merten, Wessley B., Schizas, Nikolaos V., Craig, Matthew T., Appeldoorn, Richard S., and Hammond, Donald L.

Subjects
Gene expression -- Observations, Mahi mahi -- Genetic aspects, Zoology and wildlife conservation
Abstract

Abstract--The dolphinfish (Coryphaena hippurus) is of major recreational and commercial importance, and landings have increased in recent years around Puerto Rico, throughout the Caribbean Sea, and along the U.S. East [...]

Published
2015
Full Text
View/download PDF

9. Diel vertical movements of adult male dolphinfish (Coryphaena hippurus) in the western central Atlantic as determined by use of pop-up satellite archival transmitters

Author

Merten, Wessley, Appeldoorn, Richard, Rivera, Roberto, and Hammond, Donald

Subjects
Spatial behavior in animals -- Research, Mahi mahi -- Research, Biological sciences
Abstract

The vertical movements of six adult male dolphinfish (Coryphaena hippurus) (95-120 cm estimated fork length), caught using standard sportfishing methods, were investigated using high-rate single-point pop-up satellite archival transmitters from 2005 to 2011 in the western central Atlantic. Data revealed a diel activity pattern within the mixed surface layer with dives below the thermocline suggesting temperature is not a barrier to vertical movements for short periods of time. Dolphinfish were tracked for periods of 4.96-30.24 day (Σ = 83.37 day), reaching depths >200 m, and in temperatures ranging from 16.20 to 30.87 °C. The six tags allowed comprehensive vertical movement analyses by time of day, duration at depth, and based on vertical movement patterns. The longest (>60 min), deepest (>30 m), and most extensive vertical movement patterns occurred during night rather than day, with the most time spent near the surface during the day. Dolphinfish spent 66 % of their time in the surface layer (0-9.9 m) and only one individual spent 8 % of the monitoring period diving >8 °C from the maximum surface temperatures recorded while tracked. Two tags were analyzed based on lunar phase and revealed contrasting relationships between vertical movements during new and full phases. Our results suggest dolphinfish vertically shift between surface and at-depth feeding strategies to exploit aggregating epipelagic and mesopelagic prey items leading to predictable diel vertical movements., Introduction The dolphinfish (Coryphaena hippurus) is a large pelagic predator of significant economic importance to commercial and sportfishing industries and artisanal fisheries worldwide (Oxenford and Hunte 1986). In the western [...]

Published
2014
Full Text
View/download PDF

11. Use of video monitoring to quantify spatial and temporal patterns in fishing activity across sectors at moored fish aggregating devices off Puerto Rico

Author

Merten, Wessley, Rivera, Roberto, Appeldoorn, Richard, Serrano, Kelvin, Collazo, Omar, Jimenez, Nilda, and Federal Aid in Sport Fish Restoration (Dingell-Johnson) programme of the United States Fish and Wildlife Service grants

Subjects
fish aggregating devices, fishery-independent survey, video monitoring, small-scale fisheries, recreational fisheries, Caribbean Sea, sistemas de agregadores de peces, estudios independientes de pesca, evaluaciones utilizando video, pesquería artesanal, pesquería recreativa, mar Caribe
Abstract

A key challenge in small-scale fisheries that use moored fish aggregating devices (mFADs) is the ability to accurately quantify multi-sector fishing activity through fishery-independent methods. Here, we present a novel fishery-independent assessment of multi-sector fishing activity associated with a newly developed open access mFAD programme off San Juan, Puerto Rico. We identified three fishing sectors (recreational, charter and commercial) and 158 individual fishing vessels that routinely operated in the vicinity of the mFADs. The results indicate that daytime fishing activity varied by time of day, day of week, location and sector. During fishing tournaments, the data revealed that fishing activity increased threefold; across monitoring periods, for-hire charter vessels were the most consistent day-to-day user segment, and recreational activity peaked on weekends. Our study represents a new technique for rapidly identifying and detecting multi-sector fishing activity near mFADs and highlights the potential to gather comparable data wherever mFADs are deployed. The results are used to discuss how this technique can be used to assess the performance of mFADs to identify sector overlap and guide management in determining deployment patterns and facilitate the design of cost-effective surveys to estimate mFAD vessel activity, and potentially catch, of mFAD-associated species., Un reto crucial en las pesquerías artesanales que utilizan los sistemas de agregadores de peces fijos (mFAD, por sus siglas en inglés) es el poder cuantificar con certeza la actividad pesquera multisectorial a través de métodos independientes de la pesca. En este estudio presentamos un innovador análisis independiente de la pesca para la actividad de pesca multisectorial asociada a los nuevos mFAD establecidos en Puerto Rico. Se identificaron 3 sectores pesqueros (recreacional, de alquiler y comercial) y 158 embarcaciones que rutinariamente pescaban alrededor de los mFAD. Los resultados muestran que la actividad pesquera diurna variaba por hora del día, día de la semana, lugar y sector. Durante torneos de pesca la actividad pesquera se triplicó, a lo largo de los periodos evaluados los botes de alquiler mostraron mayor consistencia por día y la actividad recreativa aumentó durante el fin de semana. Nuestro estudio plantea una nueva técnica para identificar rápidamente y detectar actividad multisectorial pesquera cerca de los mFAD y resalta el potencial de tomar datos comparables en otros lugares donde se coloquen los mFAD. Los resultados se utilizan para discutir cómo esta técnica puede ser utilizada para evaluar la ejecutoria de los mFAD, identificar solape de uso por varios sectores y guiar las decisiones en cuanto a los patrones para colocar los mFAD y facilitar el diseño de estudios costo efectivos para estimar la actividad de embarcaciones y el potencial de captura de peces alrededor de los mFAD.

Published
2018
Full Text
View/download PDF

13. DOLPHINFISH RESEARCH PROGRAM ADDS GUATEMALA.

Author

MERTEN, WESSLEY

Subjects
TUNA fishing, SUSTAINABLE fisheries, LIFE history theory, YELLOWFIN tuna, POLITICAL participation
Abstract

For me, however, dorado is the research subject - not because I don't enjoy catching marlin and sails, but because dorado is one of the most poorly understood and documented fish species in our oceans, especially off the coast of Guatemala. DEPARTMENTS For most anglers who venture to Guatemala's Casa Vieja Lodge, dorado is not likely the target species. Fortunately, Casa Vieja supports enabling a sustainable dorado fishery, and recently - with funding provided by the Guy Harvey Foundation and sponsors of the Dolphinfish Research Program, a globally recognized international tagging program for dolphinfish - Casa Vieja's anglers began to tag and release small dorado to aid in data collection on this species throughout the region. [Extracted from the article]

Published
2023

19. EXPANDING THE DOLPHINFISH RESEARCH PROGRAM.

Author

MERTEN, WESSLEY

Subjects
DOLPHINS, MARINE biology, PERU Current, MARINE resources, SIZE of fishes, HAMMERHEAD sharks, LIFE history theory, BOTTLENOSE dolphin
Published
2022

20. TAG TARGET: DOLPHIN.

Author

MERTEN, WESSLEY

Subjects
SIZE of fishes, FISH tagging, WILDLIFE conservation, RECREATIONAL mathematics, BOAT chartering
Abstract

One of the most prolific offshore species finally gets some attention Many recreational anglers will not catch 4,000 dolphin in their lifetime, let alone tag and release that same number in the name of conservation and science. "Since I began fishing for dolphin in the Keys in the 1990s, we would catch larger dolphin more often than today", Gates says. This data also demonstrates that East Coast anglers will benefit by releasing small dolphin in order to provide the fish an opportunity to return the following year as gaffer-size dolphin. [Extracted from the article]

Published
2021

Catalog

Books, media, physical & digital resources
See catalog results