scholarly journals Marine Habitat Recovery of Five Derelict Gear Removal Sites in Puget Sound

2018 ◽  
Author(s):  
Jeffrey June ◽  
Kyle Antonelis

Reports on the findings of a post-derelict net removal habitat monitoring project in Puget Sound. This study had three objectives. First was to document impacts ofderelict fishing gear on marine habitats. Second was to monitor the recovery of thesehabitats after derelict fishing gear was removed. Third was to monitor sites for newlylost fishing gear to determine re-accumulation rates at these sites. This study showed that marine habitat service functions are negatively affected by derelict fishing gear. It showed that natural ocean processes succeed in restoring these service functions within a single growing season after derelict fishing gear removal for areas dominated by kelp. Eelgrass beds take longer to recover, but can improve by 30% in less than a year.

2018 ◽  
Author(s):  
Kyle Antonelis ◽  
James Selleck ◽  
Joan Drinkwin ◽  
Annika Saltman ◽  
Dan Tonnes ◽  
...  

Derelict fishing gear is a known stressor to rockfish populations in the Washington waters of the Salish Sea, including two species currently federally protected under the Endangered Species Act. In Washington and British Columbia, rockfish bycatch in actively fished (non-derelict) prawn traps has been documented in spot prawn test fisheries conducted by state and provincial government, and both live and dead rockfish have been found in derelict prawn traps encountered during derelict fishing gear removal operations in Washington. This study calculates rockfish bycatch rates in actively fishing prawn traps and provides preliminary trap loss rates for both commercial and recreational fisheries. Rockfish bycatch rates were determined through analysis of Washington Department of Fish and Wildlife (WDFW) Spot Prawn Test Fishery Data collected from 2004 to 2013. Data from WDFW creel surveys were used to update preliminary prawn trap loss rates. Interviews with WDFW marine enforcement officers were conducted to estimate the number of lost traps that are recovered before becoming derelict. The overall rockfish catch rates in Washington waters of the Salish Sea were 0.023 rockfish per trap drop, with considerable spatial and temporal variability. The lowest catch rates were consistently seen in Marine Area 7 (San Juan Islands and North Puget Sound); while the highest catch rates were seen in Marine Area 11 (south-central Puget Sound). The trap loss rate estimated for the recreational fishery is 2.33% of all traps fished. We estimate that over the years 2012 and 2013 an average of 653 recreational prawn traps became derelict each year. The accumulation of derelict prawn traps has a mostly unknown effect on benthic habitats of Puget Sound, which warrants additional research. While rockfish bycatch and prawn trap loss rates reported here are low, our findings support evaluating methods to reduce rockfish encounters with prawn traps.


2013 ◽  
Vol 15 (1) ◽  
pp. 189 ◽  
Author(s):  
M. VACCHI ◽  
M. MONTEFALCONE ◽  
V. PARRAVICINI ◽  
A. ROVERE ◽  
P. VASSALLO ◽  
...  

Spatial modelling is an emerging approach to the management of coastal marine habitats, as it helps understanding and predicting the results of global change. This paper reviews critically two recent examples developed in Liguria, an administrative region of NW Italy. The first example, aiming at predicting habitat status depending on pressures, provides managers with the opportunity of envisaging different scenarios for the consequences of coastal development choices. The second example defines the status of an important Mediterranean coastal marine habitat (Posidonia oceanica meadows) under natural conditions, allowing for quantifying human impacts on regressed meadows. Both modelling approaches are useful to define the targets of coastal management, and may help choosing the best management option. Well-planned and sustained monitoring is essential to model validation and improvement.


10.29007/npz9 ◽  
2019 ◽  
Author(s):  
Ramón Aranda ◽  
Hugo Carlos

Fishing is an ancient practice that dates back to at least the beginning of the Upper Paleolithic period about 40,000 years ago. Nowadays, Fishing is one of the most important activities, as it provides a source of food and economic income worldwide. A key challenge in ecology and conservation is to decrease the Illegal, Unreported and Unregulated fishing (IUU). IUU fishing depletes fish stocks, destroys marine habitats, distorts competition, puts honest fishers at an unfair disadvantage, and weakens coastal communities, particularly in developing countries. One strategy to decrease the IUU fishing is monitoring and detecting the fishing vessel behaviors. Satellite–based Automatic Information Systems (S– AIS) are now commonly installed on most ocean–going vessels and have been proposed as a novel tool to explore the movements of fishing fleets in near real time. In this article, we present a dictionary–based method to classify, by using AIS data, between two fishing gear types: trawl and purse seine. The data was obtained from Global Fishing Watch. Our experiments show that our proposal has a good performance in classifying fishing behaviors, which could help to prevent overexploit and improve the strategies of the fisheries management.


Author(s):  
D. Ganesh ◽  
S.MD. Saleem Naveed ◽  
M. Kalyan Chakravarthi

Aquaculture is major occupation for the humans living at coastal areas. The fresh water cultivation of the certain species is prominent in tropical and sub-tropical climates. Here the proposed work shows the relation-ship between the growth of the certain species of marine habitats and the factors affecting their growth with respect to the medium of their living. Advancement of embedded systems in aquaculture leads to new innovations of monitoring and controlling the various parameters. Here the embedded system based application is used, through which the monitoring and controlling of the light is done with the help of LabVIEW based PI controller as well as Fuzzy controller for the effective and healthy growth of the marine habitat. The Designed controllers are energy efficient based controller for controlling the Light Source (LS) via appropriate lighting control levels. The controlling and managing of the system is based on the present light intensity with the help of virtual controller. The proposed work involves the designing and implementation of PI controller and the fuzzy controller for the real time setup to monitor and control the process for optimal and feasible solution.


Author(s):  
M. Doukari ◽  
K. Topouzelis

Abstract. Marine habitat mapping is essential for updating existing information, preserving, and protecting the marine environment. Unmanned Aerial Systems (UAS) are an important tool for monitoring and mapping coastal and marine environment because of their ability to provide very high-resolution aerial imagery.Environmental conditions have a critical role in marine mapping using UAS. This is due to the limitations of UAS surveys in coastal areas, i.e. the environmental conditions prevailing in the area. The limitations of weather and oceanographic conditions affecting the quality of marine data led to the creation of a UAS protocol for the acquisition of reliable marine information. The produced UAS Data Acquisition Protocol consists of three main categories: (i) Morphology of the study area, (ii) Environmental conditions, (iii) Flight parameters. These categories include the parameters that must be considered for marine habitat mapping.The aim of the present study is the accuracy assessment of the UAS protocol for marine habitat mapping through experimental flights. For the accuracy assessment of the UAS protocol, flights on different dates and environmental conditions were conducted, over a study area. The flight altitude was the same for all the missions, so the results were comparable. The high-resolution orthophoto maps derived from each date of the experiment were classified. The classification maps show several differences in the shape and size of the marine habitats which are directly dependent on the conditions that the habitats were mapped. A change detection comparison was conducted in pairs to examine the exact changes between the classified maps.The results emphasize the importance of the environmental conditions prevailing in an area during the mapping of marine habitats. The present study proves that the optimal flight conditions that are proposed of the UAS Data Acquisition protocol, respond to the real-world conditions and are important to be considered for an accurate and reliable mapping of the marine environment.


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