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Inherent differences between baited remote video versus diver-operated video survey methodologies may influence their ability to detect effects of fishing. Here, the ability of no-take zones (NTZs) to provide protection for legal-sized fish from targeted species within the Ningaloo Marine Park (NMP) was assessed using both baited remote underwater stereo-video (stereo-BRUV) and diver-operated stereo-video (stereo-DOV). The relative abundance of legal-sized individuals of three recreationally targeted fish species, spangled emperor Lethrinus nebulosus, chinaman cod Epinephelus rivulatus and goldspotted trevally Carangoides fulvoguttatus, were examined using both methodologies inside and outside six NTZs across the NMP. Stereo-BRUVs found positive effects of protection on the relative abundance of legal-size C. fulvoguttatus and L. nebulosus in NTZs. Stereo-DOVs, however, did not detect any differences in relative abundances and sizes of these species between areas opened and closed to fishing. These contrasting results suggest that choice of sampling methodology can influence interpretations of the ability of NTZs to provide adequate levels of protection for target species. Our results suggest that stereo-BRUVs are a superior technique to stereo-DOVs for assessing the effectiveness of no-take zones for protection of fishery target species, reflecting bait attraction and an absence of diver influence on fish behaviour.

Declines in abundance of sea snakes have been observed on reefs throughout the Indo-Pacific, although the reasons are unknown. To date, surveys have occurred on shallow reefs, despite sea snakes occurring over a large depth range. It is not known if populations of sea snakes in deep habitats have undergone similar declines. To address this, we analysed deep-water video data from a historical hotspot of sea snake diversity, Ashmore Reef, in 2004, 2016, and 2021. We collected 288 hours of video using baited remote underwater videos and a remotely operated vehicle at depths between 13 and 112 m. We observed 80 individuals of seven species with Aipysurus laevis (n = 30), Hydrophis peronii (n = 8), and H. ocellatus (n = 6) being the most abundant. Five of the species (A. duboisii, A. apraefrontalis, H. ocellatus, H. kingii, and Emydocephalus orarius) had not been reported in shallow waters for a decade prior to our study. We found no evidence of a decline in sea snakes across years in deep-water surveys, although abundances were lower than those in early shallow-water surveys. A comparison of BRUVS data from 2004 and 2016 was consistent with the hypothesis that predation by sharks may have contributed to the loss of sea snakes in shallow habitats. Our study highlights the use of underwater video to collect information on sea snakes in the mesophotic zone and also suggests that future monitoring should include these depths in order to capture a more complete representation of habitats occupied.

Walkers spot bull shark as it swims near Perth marina - video.

Walkers spot bull shark as it swims near Perth marina - video.

Amazing Video of Dutch Marines Saving German Cargo Ship from Somali Pirates - Helmet Cam.

Humpback dolphins offer gifts in rare courtship ritual - video.

Piracy declines off Somali coast (VIDEO).

Cull Kill Includes Small Tiger Sharks along with Intended Victims [Video].

Explorers to send 1st live video broadcast from ocean depths.

VIDEO: Royal Australian Navy frigate seizes $400m of hashish in waters off Middle East.

Baby whale shark rescued from gillnet in India (VIDEO).

Just a month after the start of the Vendée Globe, on 6th December in the middle of the Indian Ocean to the north of the CROZET Islands, Kito DE PAVANT and his Bastide Otio hit an unidentified floating object. The damage was fatal for the boat and the skipper was forced to abandon the race and his monohull.... Fortunately, the French vessel, the MARION-DUFRESNE, which delivers supplies to the French islands in the Antarctic and Southern Ocean, was sailing close to the area when the incident happened. Kito was rescued and taken aboard the ship, which continued her delivery trip. A few months later, they were able to watch the videos recorded on the hard disk aboard the boat, and discovered that the unidentified object was in fact a sperm whale, which was clearly visible in the wake of the boat. You can watch the video here. Hang on tight!

The silver-lipped pearl oyster, Pinctada maxima, is the primary species used for the culture of pearls in the Indo-Pacific region. The Western Australian fishery relies on wild-caught animals, and as such, knowledge of the status and distribution of P. maxima underpins sustainable management of the fishery. Eighty Mile Beach, in tropical Western Australia, is the key harvest area for P. maxima, with oysters collected by divers to depths of ∼35 m, although there are anecdotal accounts of oysters beyond diving depths. Image-based, and acoustic methods were used to elucidate distribution patterns of P. maxima off Eighty Mile Beach, including data from 862 km2 of multibeam survey and 119 towed video transects spanning an area from the 20 to 100 m contour lines. We quantified habitat characters including depth, substrate, and benthic community composition associated with pearl oyster distribution. Multibeam sonar data was also coupled with towed video data to produce predictive statistical models of P. maxima habitat. We found P. maxima to depths of 76 m, although more than 90% of individuals occurred shallower than 40 m and less than 2% were found deeper than 50 m. Oysters occupied flat, sandy habitats with neighbouring benthic communities of filter feeders (>98% of observations). These results show P. maxima predominantly occurs in depths <40 m, with no evidence that extensive populations extend into deep water in the region.

Baitfishes may aggregate around megafauna such as whale sharks (Rhincodon typus) to gain protection from larger predatory fishes. Here, we used videos from deployments of animal-borne cameras on whale sharks and provided by tourism operators at Ningaloo Reef in Western Australia to document large schools of trevally (Carangidae spp.) consuming entire schools of baitfishes (Carangidae spp.) swimming with whale sharks within 2-45 s. These videos showed that small baitfishes are still very vulnerable to predatory fishes when accompanying whale sharks, refuting the hypothesis that whale sharks provide baitfishes shelter from predators. It thus seems more likely that the association between whale sharks and baitfishes may confer other advantages such as reduced costs of locomotion and/or enhanced feeding opportunities for baitfishes rather than protection from predation.

45 Filipino seafarers still held captive by Somali Pirates [VIDEO].

A community marine monitoring project is using underwater video technology to survey fish species on shallow reef systems off Albany.

A community marine monitoring project is using underwater video technology to survey fish species on shallow reef systems off Albany.

On an isolated stretch of Western Australian beach, artist Tim Pearn creates art from colourful washed-up plastic waste

On an isolated stretch of Western Australian beach, artist Tim Pearn creates art from colourful washed-up plastic waste

Octopuses are generally loners. Squids often form schools. But cuttlefish (or seacuttles if you will)…they outright just don't get along with one another. In the video below two Giant Australian Cuttlefish males that are bit cranky fight over a female. They are both flashing the characteristic Zebra "Don't F**K With Me" pattern. Make sure you watch after 2 minutes when they really throw down.

Octopuses are generally loners. Squids often form schools. But cuttlefish (or seacuttles if you will)…they outright just don't get along with one another. In the video below two Giant Australian Cuttlefish males that are bit cranky fight over a female. They are both flashing the characteristic Zebra "Don't F**K With Me" pattern. Make sure you watch after 2 minutes when they really throw down.

Uhuru fights illegal trade with Kenya Coast Guard Service - VIDEO.

Studying stromatolites promises an insight into how life began as well as what the Earth was like 3.7bn years ago.

Studying stromatolites promises an insight into how life began as well as what the Earth was like 3.7bn years ago.

Ces îles menacées de submersion par le réchauffement climatique.