Progress,opportunities and challenges for marine conservation in the Pacific Islands

1. The people of the Pacific have long relied on the ocean for sustenance, commerce and cultural identity, which resulted in a sophisticated understanding of the marine environment and its conservation.
2. The global declines in ocean health require new and innovative approaches to conserving marine ecosystems. Marine Protected Areas (MPAs) have been shown to be a highly effective means of conserving biodiversity and managing fisheries, while also restoring and preserving overall ecosystem function.
3. Traditional ecological knowledge held by many island peoples in the Pacific is critical to the development, design and implementation of contemporary MPAs.
4. Chile's offshore islands are among the few oceanic archipelagos along the west coast of South America. These islands have cultural and ecological connections to the broader insular Pacific, yet our scientific understanding of them is extremely limited.
5. Chile has created several large-scale MPAs around their offshore archipelagos. By protecting these unique ecosystems, Chile has established itself as a global leader in marine conservation.
6. Effective management and a better understanding of social–ecological interactions are currently the biggest challenges facing MPAs in the Pacific Islands.

     

Eight urgent,fundamental and simultaneous steps needed to restore ocean health,and the consequences for humanity and the planet of inaction or delay

1. The ocean crisis is urgent and central to human wellbeing and life on Earth; past and current activities are damaging the planet's main life support system for future generations. We are witnessing an increase in ocean heat, disturbance, acidification, bio‐invasions and nutrients, and reducing oxygen levels. Several of these act like ratchets: once detrimental or negative changes have occurred, they may lock in place and may not be reversible, especially at gross ecological and ocean process scales.
2. Each change may represent a loss to humanity of resources, ecosystem function, oxygen production and species. The longer we pursue unsuitable actions, the more we close the path to recovery and better ocean health and greater benefits for humanity in the future.
3. We stand at a critical juncture and have identified eight priority issues that need to be addressed in unison to help avert a potential ecological disaster in the global ocean. They form a purposely ambitious agenda for global governance and are aimed at informing decision‐makers at a high level. They should also be of interest to the general public.
4. Of all the themes, the highest priority is to rigorously address global warming and limit surface temperature rise to 1.5°C by 2100, as warming is the pre‐eminent factor driving change in the ocean. The other themes are establishing a robust and comprehensive High Seas Treaty, enforcing existing standards for Marine Protected Areas and expanding their coverage, especially in terms of high levels of protection, adopting a precautionary pause on deep‐sea mining, ending overfishing and destructive fishing practices, radically reducing marine pollution, putting in place a financing mechanism for ocean management and protection, and lastly, scaling up science/data gathering and facilitating data sharing.
5. By implementing all eight measures in unison, as a coordinated strategy, we can build resilience to climate change, help sustain fisheries productivity, particularly for low‐income countries dependent on fisheries, protect coasts (e.g. via soft‐engineering/habitat‐based approaches), promote mitigation (e.g. carbon storage) and enable improved adaptation to rapid global change.

     

Review of climate change impacts on marine fisheries in the UK and Ireland

相似文献   

Marine protected areas invaded by floating anthropogenic litter: An example from the South Pacific

相似文献   

Puffins reveal contrasting relationships between forage fish and ocean climate in the North Pacific

Long‐term studies of predator food habits (i.e., ‘predator‐based sampling’) are useful for identifying patterns of spatial and temporal variability of forage nekton in marine ecosystems. We investigated temporal changes in forage fish availability and relationships to ocean climate by analyzing diet composition of three puffin species (horned puffin Fratercula corniculata, tufted puffin Fratercula cirrhata, and rhinoceros auklet Cerorhinca monocerata) from five sites in the North Pacific from 1978–2012. Dominant forage species included squids and hexagrammids in the western Aleutians, gadids and Pacific sand lance (Ammodytes personatus) in the eastern Aleutians and western Gulf of Alaska (GoA), and sand lance and capelin (Mallotus villosus) in the northern and eastern GoA. Interannual fluctuations in forage availability dominated variability in the western Aleutians, whereas lower‐frequency shifts in forage fish availability dominated elsewhere. We produced regional multivariate indicators of sand lance, capelin, and age‐0 gadid availability by combining data across species and sites using Principal Component Analysis, and related these indices to environmental factors including sea level pressure (SPL), winds, and sea surface temperature (SST). There was coherence in the availability of sand lance and capelin across the study area. Sand lance availability increased linearly with environmental conditions leading to warmer ocean temperatures, whereas capelin availability increased in a non‐linear manner when environmental changes led to lower ocean temperatures. Long‐term studies of puffin diet composition appear to be a promising tool for understanding the availability of these difficult‐to‐survey forage nekton in remote regions of the North Pacific.     

Effects of current and future climates on the growth dynamics and distributions of two riverine fishes

1. To facilitate conservation planning, there is a need for improved confidence in forecasts of climate change impacts on species distributions. Towards that end, there have been calls for the development of process-based models to test hypotheses concerning the mechanisms by which temperature shapes distribution and to corroborate forecasts of correlative models.
2. Models of temperature-dependent growth (TDG) were developed for two Australian riverine blackfishes with disjunct longitudinal distributions: Gadopsis marmoratus (occupies lower, warmer elevations) and Gadopsis bispinosus (occupies higher, cooler elevations). The models were used to (a) predict blackfish monthly and annual growth dynamics under current and future climate scenarios within different elevation bands of their current distribution, and (b) test the hypothesis that, under the current climate, the distributions of each species would be positively correlated with predicted TDG.
3. Increases in mean annual growth were forecast for both species under all warming scenarios, across all elevation bands. Both species currently occupy annual habitat temperatures below those optimal for growth. Under certain warming scenarios, the predicted increases in annual growth belie forecasts of within-year dynamics that may interact with the phenology of blackfish to impair recruitment.
4. There was not a significant positive linear relationship between predicted TDG and observed abundance among river segments for either species. Both species were strongly under-represented where annual growth rates were forecast to be optimal and over-represented where growth rates were forecast to be intermediate.
5. Confidence in forecasts of climate change impacts based on correlative models will increase when those forecasts are consistent with a mechanistic understanding of how specific drivers (e.g. water temperature) affect processes (e.g. growth). This process-based study revealed surprises concerning how future climates may affect fish growth dynamics, showing that although the blackfish distributions are correlated with temperature the temperature-dependent mechanisms underpinning that correlation require further investigation.

     

Australian sperm whales from different whaling stocks belong to the same population

1. Understanding the factors driving population structure in marine mammals is needed to evaluate the impacts of previous exploitation, current anthropogenic threats, conservation status, and success of population recovery efforts.
2. Sperm whales are characterized by a worldwide distribution, low genetic diversity, complex patterns of social and genetic structure that differ significantly within and between ocean basins, and a long history of being commercially whaled. In Australia, sperm whales from the (International Whaling Commission assigned) southern hemisphere ‘Division 5’ stock were very heavily exploited by whaling.
3. The present study assessed the potential effects of whaling on the genetic diversity of sperm whales in Australia and the population genetic structure of these whales within a global context. A combination of historical and contemporary sperm whale samples (n = 157) were analysed across six regions, from south-eastern Australia (‘Division 6’ stock in the Pacific Ocean) to south-western Australia (‘Division 5’ stock in the Indian Ocean).
4. Sperm whales sampled from the ‘Division 5’ and ‘Division 6’ stocks belong to the same population based on nuclear and mitochondrial DNA (mtDNA) analyses. Four novel sperm whale mtDNA haplotypes were identified in animals from Australian waters. Levels of genetic diversity were low in Australian sperm whales but were similar to those previously reported for populations in the Indian and Pacific Oceans.
5. Given the genetic distinctiveness of sperm whales in Australian waters from other regions in the Pacific and Indian Oceans, and the lack of recovery in population numbers, further scientific studies are needed to increase our understanding of population dynamics and the effectiveness of threat management strategies in this species.

     

Atlantic salmon in a rapidly changing environment—Facing the challenges of reduced marine survival and climate change

1. Atlantic salmon populations have declined in recent decades. Many of the threats to the species during its freshwater and coastal residency periods are known, and management approaches are available to mitigate them. The global scale of climate change and altered ocean ecosystems make these threats more difficult to address.
2. Managers need to be aware that promoting strong, healthy, and resilient wild populations migrating from rivers is the optimal approach currently to reduce the impacts of changing ecosystems and low marine survival. We argue that a fundamental strategy should be to ensure that the highest number of wild smolts in the best condition leave from rivers and coastal areas to the ocean. There is great scope for water quality, river regulation, migration barriers, and physical river habitat improvements.
3. Maintenance of genetic integrity and diversity of wild populations by eliminating interbreeding with escaped farmed salmon, eliminating poorly planned stocking, and reducing impacts that reduce population sizes to dangerously low levels will support the ability of Atlantic salmon to adapt to changing environments. Reducing the impacts from aquaculture and other human activities in coastal areas can greatly increase marine survival in affected areas.
4. As most of the threats to wild salmon are the result of human activities, a focus on human dimensions and improved communication, from scientific and management perspectives, needs to be increasingly emphasized. When political and social will are coupled with adequate resources, managers often have the tools to mitigate many of the threats to wild salmon.

     

Genetic diversity,population structure,and historical demography of a highly vagile and human-impacted seabird in the Pacific Ocean: The red-tailed tropicbird,Phaethon rubricauda

1. Many seabird breeding colonies have recovered from heavy anthropogenic disturbance after conservation actions. The widely distributed red-tailed tropicbird, Phaethon rubricauda, was used as a model species to assess potential anthropogenic impacts on the genetic diversity of breeding colonies in the Pacific Ocean.
2. Cytochrome c oxidase subunit I and control region sequences analyses were conducted across the range of the species in the Pacific Ocean. The study sites were at islands without human-related disturbance (non-impacted islands) and with human-related disturbance (impacted islands). We hypothesized that (i) breeding colonies of the red-tailed tropicbird on impacted islands have lower genetic diversity compared with colonies on non-impacted islands, and (ii) breeding colonies of the red-tailed tropicbird show significant fine and broad-scale genetic structure across the Pacific Ocean. Bayesian skyline analyses were conducted to infer past changes in population sizes.
3. Genetic diversity was similar between impacted and non-impacted islands. There was significant broad-scale genetic structure among colonies separated by over 6,000 km, but a lack of significant fine-scale genetic structure within Australasia and Hawai'i, although a significant level of differentiation was found within Chile with Φ_ST analyses. Skyline analyses showed that effective population sizes remained relatively constant through time, but experienced either a slight decrease or the end of an expansion event through the last 1,000 years. These changes may be related to the arrival of humans on Pacific islands.
4. Impacted islands may have received immigrants from other relatively close islands, buffering the loss of genetic diversity. However, it is also possible that colonies have retained ancestral variation or that a large effective population size coupled with a long generation time (13 years) has prevented the loss of genetic diversity in human-impacted islands. Future research using higher-resolution markers is needed to resolve the population genetic structure of the red-tailed tropicbird in an ecological time-scale.

     

What is the ocean: A sea‐change in our perceptions and values?

1. Throughout human history, the ocean has occupied myriad cultural meanings, mythologies and practices, which were often founded on a notion of the sea as being so large and ‘powerful’ as to be immune to human impacts. These conceptions were grounded in observations from the surface or shoreline, and in periods when human activities in the ocean were more technologically and spatially limited than they are today.
2. Advancements in science and technology have significantly altered how humans interact with and access the ocean, allowing exploration and exploitation of ocean areas and processes that were previously incomprehensible. This new capacity to understand and extract from the ocean might be expected to profoundly alter human relationships to it and conceptions of it.
3. As public support and engagement with marine conservation and ‘blue economies’ stem from value and belief systems, future marine management will benefit from recognizing our historical marine relationships as context for changes in understanding, use, and the increasing environmental degradation faced by the ocean. This review focuses on perspectives of the ocean that have been held historically and queries their future persistence at this potential turning point in our relationship with the ocean.

     

How “The Blob” affected groundfish distributions in the Gulf of Alaska

We investigated the distributional shifts of groundfish in response to anomalous ocean conditions, particularly the recent anomalously warm period (2014–2016; “The Blob”), based on data from ten Gulf of Alaska bottom trawl surveys conducted by the Alaska Fisheries Science Center during 1996–2015. Six groundfish species were considered: Pacific cod (Gadus macrocephalus), arrowtooth flounder (Atheresthes stomias), walleye pollock (Gadus chalcogrammus), Pacific ocean perch (Sebastes alutus), northern rock sole (Lepidopsetta polyxystra), and southern rock sole (Lepidopsetta bilineata). Ontogenetic differences were examined by dividing data for each fish species into size classes. Our study demonstrated that after accounting for size‐specific depth preferences, the spatial responses of groundfish to anomalous ocean conditions differed by species and foraging guild in the central Gulf of Alaska. Pacific cod and arrowtooth flounder showed similar responses to ocean warming, but different responses to cooling. In general, Pacific cod moved to deeper depths in warmer years and moved to shallower depths in colder years. Arrowtooth flounder also moved deeper in warmer years. However, in colder years, large arrowtooth flounder (>40 cm) shifted toward shallower depths while smaller‐sized fish shifted toward deeper depths. In warmer years, large pollock (>30 cm) moved to deeper waters while smaller pollock (10–20 cm) moved to shallower waters. Pacific ocean perch exhibited an opposite response to thermal changes in habitat compared with Pacific cod and arrowtooth flounder. They moved deeper in colder years, but there was no clear change in depth as a function of size in response to warmer habitat.     

Regional population genetics and global phylogeography of the endangered highly migratory shark Lamna nasus: Implications for fishery management and conservation

1. The porbeagle shark Lamna nasus is a large highly migratory shark distributed in cold and temperate marine waters of the North Atlantic and Southern Hemisphere (SH). According to the International Union for Conservation of Nature, the porbeagle is assessed globally as Vulnerable and regionally as Critically Endangered in the North Atlantic and the Mediterranean Sea. This study explored, for the first time, the population genetics of L. nasus at a regional (south-east Pacific Ocean) and global scale.
2. In this study, the null hypotheses of no genetic discontinuities among populations (i) within the SH, and (ii) between the SH and Northern Hemisphere (NH) were tested. Also, the demographic history of L. nasus in different ocean basins was assessed. Two mitochondrial markers (Control Region [CR] and cox1) well suited for population genetics inferences in sharks were used.
3. Spatial–genetic analyses suggested two genetic clusters co-occurring in the south-eastern Pacific Ocean. A two-way ANOVA using the cox1 but not the CR mtDNA fragment detected an effect of genetic identity on shark body size. Phylogeographic analyses, haplotype networks, and analyses of molecular variance demonstrated genetic differences between populations from the NH and SH but not among populations in the SH.
4. Migration estimates indicated limited current maternal gene flow between the two hemispheres but high gene flow within hemispheres. Two well-defined haplotype groups with star-like shapes inhabited all ocean basins in the SH. These results could reflect a historical scenario of reproductive isolation and more recent mixture among previously isolated populations in the SH. A Bayesian skyline plot analysis indicated sudden population expansion in the SH occurring ~100–125 kya.
5. This study highlights the need for additional studies focusing on the population genomics (using nuclear markers, i.e. single nucleotide polymorphisms) and the general biology of L. nasus to explore the existence of genetically dissimilar populations in the SH. Such studies will help implementing efficient genetic monitoring programmes.

     

A review of climate change and the implementation of marine biodiversity legislation in the United Kingdom

相似文献   

Reefs and islands of the Chagos Archipelago,Indian Ocean: why it is the world's largest no‐take marine protected area

相似文献   

Historical abundance and distributions of Salpa thompsoni hot spots in the Southern Ocean and projections for further ocean warming

1. In contrast to Antarctic krill Euphausia superba, Antarctic salps (Salpa thompsoni) respond positively to warmer water temperatures and have the ability to create massive blooms under favourable conditions. Therefore, they can compete with krill for primary production. Over the last three decades, significant variability in S. thompsoni occurrence has been observed as a response to the environmental fluctuations of the Southern Ocean ecosystem (e.g. changes in sea surface temperature and ice-cover shrinkage around the cold Antarctic waters).
2. This study presents historical abundance data of salps from the south-west Atlantic Sector of the Southern Ocean, covering a time span of 26 years. These data allow tracking of fluctuations in Antarctic salp abundance and their distribution with bottom depth, temperature, and ice conditions, aiming to reveal salp hot spots and to predict the future range of S. thompsoni distribution with upcoming climate warming in the next 50 years.
3. Results showed the highest salp density in shallow shelf waters with ice cover and low temperatures between 1 and −1°C. In the studied area, S. thompsoni hot spots were located mostly around Elephant Island, but also the islands around Brensfield and Gerlache Straits, as well as to the south near the Bellingshausen Sea. Inferences made of future salp distribution suggest that the range of S. thompsoni will move southwards, enlarging their habitat area by nearly 500,000 km², which may have significant implications on the whole Antarctic food web. The information presented herein may be used for Antarctic ecosystem management, protection, and conservation.

     

Variation in the distribution of ocean shrimp (Pandalus jordani) recruits: links with coastal upwelling and climate change

In this analysis, an atypical northward shift in the distribution of age‐1 ocean shrimp (Pandalus jordani) recruits off Oregon in 2000 and 2002–2004 was linked to anomolously strong coastal upwelling winds off southern Oregon (42°N latitude) in April–July of the year of larval release (t?1). This is the first clear evidence that strong upwelling winds can depress local recruitment of ocean shrimp. Regression analysis confirmed a long‐term negative correlation between log_e of ocean shrimp recruitment and April sea level height (SLH) at Crescent City, California, in the year of larval release, for both northern and southern Oregon waters. The regional pattern of ocean shrimp catches and seasonal upwelling winds showed that, although the timing of the spring transition as reflected in April SLH drives ocean shrimp recruitment success off Oregon generally, the strength and consistency of spring upwelling limits the distribution of large concentrations of ocean shrimp at the southern end of the northern California/Oregon/Washington area. A northward shift in 1999 and 2001–03 in the northern edge of this ‘zone of maximum upwelling’ is the likely cause of the weak southern Oregon recruitment and resulting atypical distribution of ocean shrimp observed off Oregon in 2000 and 2002–04, with a return to a more typical catch distribution as spring upwelling moderated in subsequent years. It is noted that a northward shift in the conditions that produce strong and steady spring upwelling winds is consistent with many predictions of global climate models under conditions of global warming.     

Climate change and the evolution of reef fishes: past and future

Predicting the impacts of ocean warming and acidification on marine ecosystems requires an evolutionary perspective because, for most marine species, these environmental changes will occur over a number of generations. Acclimation through phenotypic plasticity and adaptation through genetic selection could help populations of some species cope with future warmer and more acidic oceans. Coral reef species are predicted to be some of the most vulnerable to climate change because they live close to their thermal limits. Yet, their evolutionary history may indicate that they possess adaptations that enable them to cope with a high CO₂ environment. Here, we first explore the evolutionary history of reef fishes and how their history has shaped their physiological adaptations to environmental temperatures and pCO₂. We examine current‐day thermal and CO₂ environments experienced by coral reef fishes and summarize experimental studies that have tested how they respond to elevated temperatures and pCO₂ levels. We then examine evidence for acclimation and adaptation to projected ocean warming and acidification. Indeed, new studies have demonstrated the potential for transgenerational plasticity and heritable genetic variation that would allow some fishes to maintain performance as the oceans warm and become more acidic. We conclude by outlining management approaches – specifically those that can help preserve genetic variation by maintaining population size – to enhance the potential for genetic adaptation to climate change.     

Review of climate change impacts on marine fish and shellfish around the UK and Ireland

相似文献   

Review of climate change impacts on marine aquaculture in the UK and Ireland

相似文献   

Geometric morphometric methods as complementary tools to investigate variability in common dolphins (Delphinus sp.) using museum specimens

1. The common dolphin (Delphinus delphis) has a worldwide distribution, from tropical to temperate seas and oceans. Because of the high degree of geographic variation, the taxonomy of the species is still uncertain.
2. Skulls from 195 museum specimens from nine marine areas were examined using two- and three-dimensional geometric morphometrics. Size and shape variations were analysed using univariate and multivariate statistics among and within areas.
3. Sexual dimorphism and ontogenetic allometry were explored in the largest sample from the south-eastern Pacific Ocean, and significant differences in size between males and females, and effects on shape from sex and marine area interactions were detected, showing that the extreme traits of larger males were a consequence of continuous growth along a common allometric trajectory.
4. A first multivariate ordination of three-dimensional data allowed the detection of highly derived long-beaked morphotypes that were identified as D. delphis tropicalis.
5. An analysis of large-scale shape variation on two-dimensional data in the remaining 142 short-beaked specimens highlighted significant differences between southern and northern stocks, mainly in terms of the relative proportion of the rostrum and the braincase, suggesting an adaptive convergence irrespective of ocean of origin. The results also revealed a clear distinction in the skull shape of the north-eastern Pacific Ocean stock and a large shape variation in the Mediterranean stock.
6. Geometric morphometrics of the skull provided a highly accurate method to investigate the geographic variability in common dolphins, confirming previous genetic findings and highlighting new patterns of likely adaptive variations deserving further study, at both large and small geographic scales.