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The global lockdown to mitigate COVID-19 pandemic health risks has altered human interactions with nature. Here, we report immediate impacts of changes in human activities on wildlife and environmental threats during the early lockdown months of 2020, based on 877 qualitative reports and 332 quantitative assessments from 89 different studies. Hundreds of reports of unusual species observations from around the world suggest that animals quickly responded to the reductions in human presence. However, negative effects of lockdown on conservation also emerged, as confinement resulted in some park officials being unable to perform conservation, restoration and enforcement tasks, resulting in local increases in illegal activities such as hunting. Overall, there is a complex mixture of positive and negative effects of the pandemic lockdown on nature, all of which have the potential to lead to cascading responses which in turn impact wildlife and nature conservation. While the net effect of the lockdown will need to be assessed over years as data becomes available and persistent effects emerge, immediate responses were detected across the world. Thus, initial qualitative and quantitative data arising from this serendipitous global quasi-experimental perturbation highlights the dual role that humans play in threatening and protecting species and ecosystems. Pathways to favorably tilt this delicate balance include reducing impacts and increasing conservation effectiveness.

Predictions of the distribution of groundfish species are needed to support ongoing marine spatial planning initiatives in Canadian Pacific waters. Data to inform species distribution models are available from several fishery-independent surveys. However, no single survey covers the entire region and different gear types are required to survey the range of relevant habitat. Here, we demonstrated a method for integrating presence-absence data across surveys and gear types that allows us to predict the coastwide distributions of 65 groundfish species in British Columbia. Our model leverages data from multiple surveys to estimate how species respond to environmental gradients while accounting for differences in survey catchability. We find that this method has two main benefits: (1) it increases the accuracy of predictions in data-limited surveys and regions while having negligible impacts on accuracy when data are already sufficient, and (2) it reduces uncertainty, resulting in tighter confidence intervals on predicted occurrences. These benefits are particularly relevant in areas of our coast where our understanding of habitat suitability is limited due to a lack of spatially comprehensive long-term groundfish surveys. Key words: demersal fish, species distribution modelling, integrated model, spatiotemporal random field, species richness, Introduction Coastwide predictions of the distribution of groundfish species are needed to support ongoing marine spatial planning (e.g., PNCIMA 2017) and oil spill response planning in Canada's Pacific Region. Data [...]

Quantifying connectivity between endangered or threatened marine populations is critical information for management and conservation, especially where abundance and productivity differ among such populations. Spatial patterns of such connectivity depend not only on extrinsic factors such as oceanography and bathymetry but also on intrinsic species‐specific factors such as life history, demography and the location of glacial refugia. Nevertheless, population structure is often inferred from related or ecologically similar species. For example, the population structure in most rockfish species (Sebastes spp.) in the Salish Sea and the US West Coast is currently inferred from genetic data of three species that are known to hybridise in Puget Sound. Here, we determined the population structure and connectivity in five Puget Sound Rockfish species (Black [Sebastes melanops], Yellowtail [S. flavidus], Redstripe [S. proriger], Greenstriped [S. elongatus], and Puget Sound Rockfish [S. emphaeus]) from over 12,000 restriction‐site associated DNA sequencing (RADseq) loci. We found species‐specific patterns of genetic differentiation, attributable to both extrinsic and intrinsic factors. Specifically, Black and Puget Sound rockfishes showed no genetic differentiation; Yellowtail and Greenstriped rockfishes were structured according to known geographic barriers; and Redstripe Rockfish revealed evidence for temporal genetic differentiation, suggesting irregular recruitment influences population structure. Only Yellowtail Rockfish followed the federal DPS boundaries generally assumed for rockfish, further emphasizing the importance of species‐specific management for the effective recovery and management of these rockfish populations and of marine species in general. [ABSTRACT FROM AUTHOR]

Many species of fishes around the world are soniferous. The types of sounds fishes produce vary among species and regions but consist typically of low-frequency (< 1.5 kHz) pulses and grunts. These sounds can potentially be used to monitor fishes non-intrusively and could complement traditional monitoring techniques. However, the significant time required for human analysts to manually label fish sounds in acoustic recordings does not yet allow passive acoustics to be used as a viable tool for monitoring fishes. In this paper, we compare two different approaches to automatically detect fish sounds. One is a more traditional machine learning technique based on the detection of acoustic transients in the spectrogram and the classification using Random Forest (RF). The other is using a deep learning approach and is based on the classification of overlapping segments (0.2 s) of spectrogram using a ResNet18 Convolutional Neural Network (CNN). Both algorithms were trained using 21,950 manually annotated fish and non-fish sounds collected from 2014 to 2019 at five different locations in the Strait of Georgia, British Columbia, Canada. The performance of the detectors was tested on part of the data from the Strait of Georgia that was withheld from the training phase, data from Barkley Sound, British Columbia, and data collected in the Port of Miami, Florida, United States. The CNN performed up to 1.9 times better than the RF (F1 score: 0.82 vs. 0.43). In some cases, the CNN was able to find more faint fish sounds than the analyst and performed well in environments different from the one it was trained in (Miami F1 score: 0.88). Noise analysis in the 20--1,000 Hz frequency band shows that the CNN is still reliable in noise levels greater than 130 dB re 1 μPa in the Port of Miami but becomes less reliable in Barkley Sound past 100 dB re 1 μPa due to mooring noise. The proposed approach can efficiently monitor (unidentified) fish sounds in a variety of environments and can also facilitate the development of species-specific detectors. We provide the software FishSound Finder, an easy-to-use open-source implementation of the CNN detector with detailed documentation. [ABSTRACT FROM AUTHOR]

Compliance with spatial fishing regulations (e.g., marine protected areas, fishing closures) is one of the most important, yet rarely measured, determinants of ecological recovery. We used aerial observations of recreational fishing events from creel surveys before, during, and after 77 Rockfish Conservation Areas (RCAs) were established in British Columbia, Canada. There was no evidence of a change in fishing effort in 83% of the RCAs, and effort in five RCAs increased after establishment. Fishing effort in open areas adjacent to the RCAs declined with time and was higher than effort in the RCAs in all 3 years. Next, we used compliance data for 105 RCAs around Vancouver Island to model the drivers of compliance. Compliance was related to the level of fishing effort around the RCA, the size and perimeter-to-area ratio of RCAs, proximity to fishing lodges, and the level of enforcement. Noncompliance in RCAs may be hampering their effectiveness and impeding rockfish recovery. Education and enforcement efforts to reduce fishing effort inside protected areas are critical to the recovery of depleted fish stocks.

Rockfish, particularly yelloweye (Sebastes ruberrimus) and quillback (Sebastes maliger), are vulnerable to overfishing because they mature late and have affinity for shallow water (50-200 m) habitats. Because studies relating habitat characteristics with the distribution and presence of rockfishes at large scales (100s of kilometres) remain scarce, we sought to investigate the relationships between benthic characteristics with the presence-absence and abundance of rockfishes caught in longline surveys in nearshore waters of southern British Columbia. Habitat parameters were calculated from a 20 m resolution bathymetry layer. Yelloweye and quillback were examined separately and combined with 19 other rockfish species in a species aggregate (total rockfish); occurrence data were fitted with generalized linear mixed effects models, and abundance data were fitted with zero-inflated mixed effects models. The relationship between rockfish abundance with presence-absence and slope, distance to rocky habitat, and fine bathymetric position index suggests that these species prefer rocky, steep habitat. While underwater visual observation data offer measures of visual fish habitat and abundance, longline surveys may be a more cost-effective method for large-scale studies. Les sebastes, en particulier les sebastes aux yeux jaunes (Sebastes ruberrimus) et les sebastes a dos epineux (Sebastes maliger), sont vulnerables a la surpeche en raison de leur maturite tardive et de leur affinite pour les habitats d'eau peu profonde (50-200 m). Comme les etudes qui relient les caracteristiques des habitats a la repartition et a la presence de sebastes a grande echelle (centaines de kilometres) demeurent rares, nous avons examine les relations entre les caracteristiques benthiques et la presence ou l'absence et l'abondance de sebastes captures lors de releves a la palangre dans des eaux littorales du sud de la Colombie-Britannique. Les parametres associes a l'habitat ont ete calcules a partir d'une couche bathymetrique d'une resolution de 20 m. Les sebastes a yeux jaunes et les sebastes a dos epineux ont ete examines separement et combines a 19 autres especes de sebastes dans un regroupement d'especes (sebastes totaux); les donnees sur la presence ont ete calees sur des modeles lineaires generalises a effets mixtes et les donnees d'abondance ont ete calees sur des modeles a exces de zeros a effets mixtes. La relation entre l'abondance de sebastes avec presence-absence et la pente, la distance d'un habitat rocheux et l'indice de position bathymetrique fine indiquerait que ces especes preferent les habitats rocheux a pente raide. Si les donnees d'observation sous-marines visuelles fournissent des mesures visuelles de l'habitat et de l'abondance des poissons, les releves a la palangre pourraient s'averer plus economiques pour les etudes a grande echelle. [Traduit par la Redaction], Introduction Anthropogenic activities can cause water pollution, habitat degradation, and overfishing of many fish populations (Worm et al. 2006, 2009; Halpern et al. 2008) in many marine ecosystems. Consequently, a [...]

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This paper aims to provide advice on rebuilding Outside Yelloweye Rockfish (OYE) using a combination of stakeholder-manager-science consultations and closed-loop simulation modelling to test performance of a set of candidate management procedures (MPs) against specific quantitative objectives. The overall approach aims to expose the ecological and fishery consequences of specific analytical (e.g., data collection, assessment methods) and management choices (e.g., harvest control rules, target fishing mortality rates) for Yelloweye rebuilding. The key components of this work are: (i) development of two-stock hierarchical agestructured operating models for OYE that represent a range of hypotheses about natural mortality and exploitation history, (ii) testing MPs comprised of monitoring data, assessments, and harvest control rules (HCR) used to implement rebuilding policies, and (iii) evaluating performance measures that are used in determining the expected conservation performance of alternative MPs relative to stated rebuilding objectives. Alternative data scenarios produced a wide range of estimated stock status, as well as biological and management parameters, from which 4 representative operating models (OMs) (using a 1960 or 1918 start year and alternative catch scenarios) were selected for simulation testing MPs. The 4 OMs ranged in current biomass from approximately 2,600 to 8,200 t in the North (groundfish management areas 5BCDE) and 1,900 to 4,400 t in the South (groundfish management areas 3CD5A). This range is considerably wider than the statistical uncertainty within any particular OM. No single factor clearly explains the range of biomasses because natural mortality, absolute catch levels, and historical recruitments all affect biomass and recruitment estimates either directly or indirectly. The 1960 start year generally has the higher unfished and current biomass, while the lower bound commercial catch scenario leads to the lower unfished and current biomass. None of the 4 OMs indicate that either OYE stock area has been fished to less than 20% of the unfished level or below 40% of BMSY (Biomass at Maximum Sustainable Yield), as inferred in previous assessments. Model estimates of spawning biomass depletion relative to unfished levels range from 29-51% in the North, 21-43% in the South, and 27-48% coastwide. These correspond to 111-185% of BMSY in the North, 75-154% in the South, and 96-173% coastwide. The candidate MPs evaluated include three different assessment methods: i) a catch-at-age (CAA) assessment model, ii) a surplus production (SP) assessment model, and iii) an empirical rule (IDX) using survey index trends. The three assessment methods were used in combination with different harvest control rules or implementation error scenarios to create a set of candidate MPs that were simulation tested for each of the 4 OMs for North and South areas independently. Performance statistics were evaluated using combined outputs across OMs via a 50%-16.67%-16.67%-16.67% weighting scheme. Simulations of MP performance for setting future OYE total allowable catches (TACs) generally showed robust, or potentially robust, performance to a wide range of OM scenarios. The CAA MPs were tuned to achieve a target fishing mortality rate that would provide relatively stable OYE biomass over the projection period and biomass in both the North and South areas. Management procedures based on SP models or survey index trends (IDX) produced a range of increases or stable trends in future OYE biomass. The IDX MPs were tuned to avoid biomass declines in the first 10 years, which produced long-term increases or stable trends in biomass with high inter-annual catch variability. Although the SP models generally led to biomass increases, they did so because of under-estimation biases and often showed erratic patterns in TACs. It is likely that undesirable properties of IDX and SP MPs could be improved via further tuning. [ABSTRACT FROM AUTHOR]

Marine reserves networks are implemented as a way to mitigate the impact of fishing on marine ecosystems. Theory suggests that a reserve network will function synergistically when connected by dispersal, but the scale of dispersal is often unknown. On the Pacific coast of the United States and Canada, both countries have recently implemented a number of rockfish conservation areas (RCAs) to protect exploited rockfish species, but no study has evaluated the connectivity within networks in each country or between the two countries. We used isolation-by-distance theory to estimate the scale of dispersal from microsatellite data in the black rockfish, Sebastes melanops, and compared this estimate with the distance between RCAs that would protect this species. Within each country, we found that the distance between RCAs was generally within the confidence intervals of mean dispersal per generation. The distance between these two RCA networks, however, was greater than the average dispersal per generation. The data were also consistent with a genetic break between southern Oregon and central Oregon. We discuss whether additional nearshore RCAs in southern Oregon and Washington would help promote connectivity between RCA's for shallow-water rockfishes. [ABSTRACT FROM AUTHOR]