Tim J. Langlois

University of Western Australia | UWA · Oceans Institute

Both sharks and humans present a potentially lethal threat to mesopredatory fishes in coral reef systems, with implications for both population dynamics and the role of mesopredatory fishes in reef ecosystems. This study quantifies the antipredator behaviours mesopredatory fishes exhibit towards the presence of large coral reef carnivores and compa...

Context The western rock lobster fishery is recognised to be conservatively managed, with breeding stock levels estimated to be at record levels over the past decade. Despite this, anecdotal reports from commercial fishers identified an area of unexpectedly low catches in the centre of the fishery and lobsters’ biogeographic distribution. Aim To co...

Shark depredation is a complex social-ecological issue that affects a range of fisheries worldwide. Increasing concern about the impacts of shark depredation, and how it intersects with the broader context of fisheries management, has driven recent research in this area, especially in Australia and the United States. This review synthesises these r...

The effects of fishing have been documented across coral reefs worldwide. No-take marine reserves do not only act as a conservation tool but also allow an opportunity to study impacts of fishing, by acting as control sites. In addition, well-planned and well-managed no-take marine reserves (NTRs) provide conservation benefits that are essential to...

Quantifying the drivers of population size in reef sharks is critical for the development of appropriate conservation strategies. In north-west Australia, shark populations inhabit coral reefs that border growing centres of human population, industry, and tourism. However, we lack baseline data on reef sharks at large spatial scales (hundreds of km...

Many researchers have pointed to coastal environments and their use for energy production, aquaculture, and conservation as key to solving profound challenges facing humanity. Navigating this transition in ocean space necessitates tools to quantify impacts on displaced marine users, including recreational fishers. In this study, we present a novel...

Determining influences of predation and competition on community dynamics is particularly challenging in coral reef systems where interspecific interactions between many predator and prey species play out in patchy landscapes. We used ~1000 stereo-baited remote underwater video deployments (stereo-BRUVs) to assess the relative abundance and analyse...

A large (∼2450 km²) offshore (∼75 km) targeted fisheries closure (TFC) area was implemented on the North West Shelf of Australia (NWS) in 1998 as part of a suite of management controls to address overfishing concerns, and in the process to potentially mitigate any impacts of trawling to benthic habitats. Twelve years later, the benthic biota and fi...

The pelagic development stages of many marine invertebrate species dictates their spatial and temporal distribution once reaching their benthic second phase of life. This life cycle is associated with the Western Rock Lobster (Panulirus cygnus) along the coast of Western Australia. Over the past 50 years, the number of puerulus reaching the nearsho...

Dynamics of ocean boundary currents and associated shelf processes can influence onshore/offshore transport of water, critically impacting marine organisms that release long-lived pelagic larvae into the water column. The western rock lobster, Panulirus cygnus, endemic to Western Australia, is the basis of Australia's most valuable wild-caught comm...

Indices of lobster abundance and population demography are often derived from pot catch rate data and rely upon constant catchability. However, there is evidence in clawed lobsters, and some spiny lobsters, that catchability is affected by conspecifics present in pots, and that this effect is sex and size-dependent. For the first time, this study i...

Marine reserves are a key tool for the conservation of marine biodiversity, yet only ~2.5% of the world's oceans are protected. The integration of marine reserves into connected networks representing all habitats has been encouraged by international agreements, yet the benefits of this design has not been tested empirically. Australia has one of th...

Many marine fish populations have declined due to the individual or cumulative impacts of increasing water temperatures, ocean acidification, overfishing and other human-induced impacts such as land run-off, dredging and habitat alteration. Some solutions may be offered by ecosystem-based fisheries and conservation management. However, understandin...

Baited remote underwater stereo-video systems (BRUVs) are being adopted globally as a sampling method for surveying fish assemblages. The literature demonstrates that researchers are using different deployment times, rarely with justification for the time chosen. We aimed to determine the optimal deployment time of BRUVs to sample reef fish assembl...

Abstract The idea that the presence of sharks impacts the behavior of mesopredatory reef fishes is controversial and lacks clear evidence at reef‐wide scales. We compared the abundance and behavior of these reef fishes in response to the presence of reef sharks using Baited Remote Underwater Video System (BRUVS) deployments in two adjacent reef sys...

An Amendment to this paper has been published and can be accessed via a link at the top of the paper.

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 ho...

Climate change is modifying species distributions around the world, forcing some species poleward, where they can alter trophic interactions. Many tropical herbivorous fishes have successfully expanded their ranges into temperate ecosystems, and while it is clear they drive increases in herbivory rates in specific localities, little is known about...

Decades of overexploitation have devastated shark populations, leaving considerable doubt as to their ecological status1,2. Yet much of what is known about sharks has been inferred from catch records in industrial fisheries, whereas far less information is available about sharks that live in coastal habitats³. Here we address this knowledge gap usi...

Baited video systems have been widely used to assess the relative abundance and diversity of sharks in locations around the world, however they provide limited information on behaviour. We developed and pilot tested a novel experimental approach to investigate whether repeated deployments of baited video systems in the same location could generate...

Understanding the drivers of exploited fish abundance distributions is key to successful natural resource management, but it is costly to obtain this information at large spatio-temporal scales relevant to management. We used small programmable automated cameras (POTBots) deployed in commercial rock lobster fisher’s pots, during normal fishing acti...

Predators can exert strong ecological effects on their prey either via consumption or by altering their behaviour and morphology. In marine systems, predators and their prey co‐occur in a three‐dimensional environment, but to date predator–prey studies have largely focussed on behaviours of prey on horizontal (distance from shelter) rather than ver...

The tropicalization of temperate marine ecosystems can lead to increased herbivory rates, reducing the standing stock of seaweeds and potentially causing increases in detritus production. However, long-term studies analysing these processes associated with the persistence of tropical herbivores in temperate reefs are lacking. We assessed the season...

Marine recreational fisheries (MRFs) are often highly spatially heterogenous, with effort concentrated into small areas, and fisheries spanning large environmental gradients. However, spatially resolved catch data is rarely collected in MRFs, preventing the study of spatial heterogeneity in catch. This study uses recreational catch reported in 10 ×...

Shark depredation, whereby a shark consumes an animal caught by fishing gear, can cause higher mortality for target species, injury to sharks and the loss of catch and fishing gear. A critical first step towards potential mitigation is understanding this behaviour and the shark species involved, because the identity of depredating shark species is...

One of the main challenges in assessing marine biodiversity is the lack of consistent approaches to monitor it. This threatens to undermine ocean best practice in marine monitoring, as it impedes a reduction in the bias and variance of sampled data and restricts the confidence in the advice that can be given. In particular, there is potential for c...

A suite of field manuals was released by the NESP Marine Hub in early 2018 to facilitate a national monitoring framework, with a focus on seven marine sampling platforms: multibeam sonar, autonomous underwater vehicles, baited remote underwater video (pelagic and demersal), towed imagery, sleds and trawls, and grabs and box corers. These platforms...

There has been rapid uptake of stereo‐video‐based sampling techniques to collect species, abundance and body‐size information on fish assemblages and their associated habitats. Stereo‐video methods provide highly accurate estimates of body‐size, range and sampling area as well as a permanent record that can be cross‐checked or resampled for additio...

Endemic to the Indo West-Pacific region, zebra sharks (Stegostoma fasciatum) are on the International Union for Conservation of Nature endangered species list. Despite this, little is known about the reproduction behaviour or where individuals copulate. In October 2015, two zebra sharks - one male and one female - were observed on a baited remote u...

No-take marine reserves (NTRs), i.e. areas with total fishing restrictions, have been established worldwide aiming to promote biodiversity and ecosystem conservation. Brazil has 3.3% of its exclusive economic zone protected by 73 different NTRs, however, most of them currently lack scientific knowledge and understanding of their ecological role, pa...

List of species found within no-take reserves and fished areas. *Endemic from Brazilian biogeographic province [28, 81–83]; VUI = Vulnerable by International Union for Nature Protection (IUCN) Red List [84]; NTI = Near threatened by IUCN; VUBr = Vulnerable by Brazilian legislation [85]; CRBr = Critically endangered by Brazilian Legislation; Y = Tar...

Fish abundance data. (TXT)

Data used to fit the generalised additive mixed models (GAMMs). (TXT)

Shark depredation, where a shark partially or completely consumes an animal caught by fishing gear before it can be retrieved to the fishing vessel, occurs in commercial and recreational fisheries worldwide, causing a range of negative biological and economic impacts. Despite this, it remains relatively understudied compared to other fisheries issu...

Nocturnal studies of fish assemblages are relatively rare, particularly at depths greater than 100 m, despite the relevance of diel shifts in habitat usage to fisheries management. This study assesses fish diversity and abundance from remotely operated vehicle (ROV) video recordings that were collected by industry during the day and at night in the...

No-take marine reserves are essential for scientific monitoring, likely to contribute to the sustainability of targeted species, help to buffer biodiversity loss due to climate change impacts, and provide public education, tourism and diverse economic benefits to local communities. However, the establishment of no-take marine reserves has been a co...

No-take marine reserves (NTRs), i.e. areas with total fishing restrictions, have been established worldwide aiming to provide biodiversity and ecosystem conservation. Brazil has established NTRs, but currently lacks scientific knowledge and understanding of their ecological role, particularly regarding rocky reefs in subtropical regions. Consequent...

Understanding environmental drivers of fish assemblage composition is fundamental to designing useful management plans for anthropogenic activities. This study investigated the influence of suspended sediment on reef fish assemblages and habitat composition over a cross-shelf turbidity gradient in the nearshore Pilbara region of Western Australia....

Information on the potential ecological value of offshore oil and gas infrastructure is required as it reaches the end of its operational life and decisions must be made regarding the best practice option for decommissioning. This study uses baited remote underwater stereo-video systems to assess fish assemblages along an offshore subsea pipeline a...

This study investigated variations in the composition and biomass of demersal fish assemblages over a 570-metre depth gradient on the temperate, lower west coast of Australia (32° S) in the south-eastern Indian Ocean. Fish assemblages were sampled using Baited Remote Underwater Stereo Video systems (stereo-BRUVs, n=284 deployments) from shallow wat...

Remote island nations face a number of challenges in addressing concerns about shark population status, including access to rigorously collected data and resources to manage fisheries. At present, very little data are available on shark populations in the Solomon Islands and scientific surveys to document shark and ray diversity and distribution ha...

Questions asked during semi-structured interviews. (DOCX)

Raw data from BRUV and DOV surveys. (ZIP)

When production ceases, offshore oil and gas wells are taken out of service which involves safely plugging, abandoning and usually removing most of the associated subsea equipment. This process must consider impacts to marine ecosystems to meet regulatory requirement and for best environmental practice. However, there is a paucity of information gl...

Full-subsets information theoretic approaches are becoming an increasingly popular tool for exploring predictive power and variable importance where a wide range of candidate predictors are being considered. Here, we describe a simple function in the statistical programming language R that can be used to construct, fit, and compare a complete m...

The Dwesa-Cwebe Marine Protected Area (MPA) is located along the Wild Coast of South Africa, a key area for traditional subsistence fishing. Increasing pressure for access to marine resources, prompted policy changes to permit shore-based fishing for rural communities within this historically no-take MPA. The aim of the present study was to use sho...

Designated large-scale marine protected areas (LSMPAs, 100,000 or more square kilometers) constitute over two-thirds of the approximately 6.6% of the ocean and approximately 14.5% of the exclusive economic zones within marine protected areas. Although LSMPAs have received support among scientists and conservation bodies for wilderness protection, r...

Baseline ecological studies of mesophotic coral ecosystems are lacking in the equatorial Indo-West Pacific region where coral reefs are highly threatened by anthropogenic and climate-induced disturbances. Here, we used baited remote underwater video to describe benthic habitat and fish assemblage structure from 10 to 80 m depth at Apo Island, a wel...

Distribution shifts of demersal fishes are important adaptive responses to warming oceans for species' persistence. Shifts are facilitated by factors such as adult movement and dispersal of pelagic larvae to normally cooler regions, where increasing ocean temperatures are now enhancing larval and juvenile survival. However, successful recruitment (...

With over 70 contributors from 30 agencies, the NESP Marine Biodiversity Hub has developed a suite of field manuals to describe a nationally consistent and defensible approach to marine data acquisition. This manual relates to pelagic (mid-water) BRUVS, i.e. gear designed to acquire digital video imagery of macro-organisms living in the ocean’s w...

With over 70 contributors from 30 agencies, the NESP Marine Biodiversity Hub has developed a suite of field manuals to describe a nationally consistent and defensible approach to marine data acquisition. This manual relates to benthic BRUVS, i.e. gear designed to acquire imagery of demersal fish assemblages and their habitat within the field of vie...

Australia has one of the world’s largest marine estates that includes many vulnerable habitats and a high biodiversity, with many endemic species crossing a wide latitudinal range. The marine estate is used by a variety of industries including fishing, oil & gas, and shipping, in addition to traditional, cultural, scientific and recreational uses....

Ocean warming is driving species poleward, causing a ‘tropicalization’ of temperate ecosystems around the world. Increasing abundances of tropical herbivores on temperate reefs could accelerate declines in habitat-forming seaweeds with devastating consequences for these important marine ecosystems. Here we document an expansion of rabbitfish (Sigan...

Baited remote underwater stereo-video systems (stereo-BRUVs) are commonly used to sample fish assemblages across areas of differing fish densities with little consideration of how intraspecific and interspecific behaviours may influence estimates of abundance and body-size distribution. To investigate these potential biases, the current study compa...

Periodically harvested closures ( PHC s) are one of the most common forms of fisheries management in Melanesia, demonstrating multiple objectives, including sustaining fish stocks and increasing catch efficiency to support small‐scale fisheries. No studies have comprehensively assessed their ability to provide short‐term fisheries benefits across t...

Range shifts as a result of warming oceans call for evaluation of populations at the geographic range level, particularly for highly vulnerable species such as endemics and fisheries targets. We examined the influence of latitudinal temperature gradients and temperature anomalies during a 2011 marine heat wave on range-wide abundance, length freque...

Information on broad-scale movements is required for spatial management and improved conservation of large marine predators. We studied the mobility of the 4 most commercially important shark species of Western Australia (WA) using a network of acoustic receivers. Dusky sharks Carcharhinus obscurus showed very high mobility across WA. Sandbar C. pl...

Remote Operated Vehicles are routinely used to undertake inspection and maintenance activities of underwater pipelines in north-west Australia. In doing so, many terabytes of geo-referenced underwater video are collected at depths, and on a scale usually unobtainable for ecological research. We assessed fish diversity and abundance from existing RO...

Identifying the most sensitive indicators to changes in fishing pressure is important for accurately detecting impacts. Biomass is thought to be more sensitive than abundance and length, while the wariness of fishes is emerging as a new metric. Periodically harvested closures (PHCs) that involve the opening and closing of an area to fishing are the...

Shark depredation, where a shark consumes a hooked fish before it can be retrieved to the fishing vessel, can occur in recreational fisheries. This may cause higher mortality rates in target fish species, injuries to sharks from fishing gear and negatively impact the recreational fishing experience. This study quantified spatial variation and frequ...