Assessing the vulnerability of marine life to climate change in the Pacific Islands region

Abstract

Our changing climate poses growing challenges for effective management of marine life, ocean ecosystems, and human communities. Which species are most vulnerable to climate change, and where should management focus efforts to reduce these risks? To address these questions, the National Oceanic and Atmospheric Administration (NOAA) Fisheries Climate Science Strategy called for vulnerability assessments in each of NOAA’s ocean regions. The Pacific Islands Vulnerability Assessment (PIVA) project assessed the susceptibility of 83 marine species to the impacts of climate change projected to 2055. In a standard Rapid Vulnerability Assessment framework, this project applied expert knowledge, literature review, and climate projection models to synthesize the best available science towards answering these questions. Here we: (1) provide a relative climate vulnerability ranking across species; (2) identify key attributes and factors that drive vulnerability; and (3) identify critical data gaps in understanding climate change impacts to marine life. The invertebrate group was ranked most vulnerable and pelagic and coastal groups not associated with coral reefs were ranked least vulnerable. Sea surface temperature, ocean acidification, and oxygen concentration were the main exposure drivers of vulnerability. Early Life History Survival and Settlement Requirements was the most data deficient of the sensitivity attributes considered in the assessment. The sensitivity of many coral reef fishes ranged between Low and Moderate, which is likely underestimated given that reef species depend on a biogenic habitat that is extremely threatened by climate change. The standard assessment methodology originally developed in the Northeast US, did not capture the additional complexity of the Pacific region, such as the diversity, varied horizontal and vertical distributions, extent of coral reef habitats, the degree of dependence on vulnerable habitat, and wide range of taxa, including data-poor species. Within these limitations, this project identified research needs to sustain marine life in a changing climate.

A rapid approach to assessing the vulnerability of Mozambican fisheries’ species to climate change

“…In contrast, we excluded the [33] attribute on ocean acidification as there is too much uncertainty regarding its impacts [50], particularly for Mozambican fisheries species. Overall, the 12 final attributes we used corresponded closely to those of [31,33], as well as [29,36,37]. The biological trait-based attributes essentially reflect the ability of the species to withstand climate change by virtue of the resilience conferred on them by the traits.…”

“…[23] undertook projections for the tuna Katsuwonus pelamis, while [47] undertook multi-species projections for Kenya and Tanzania; these approaches were not possible for Mozambique because of the lack of resources and the large number of highly diverse species from numerous habitats. When faced with similar issues, other workers have used rapid sensitivity and/or vulnerability assessments, such as in south-east Australia [31], northeast America [33], south-western South Africa [37], Portugal [29], and the central Pacific islands [36]. The approach is a refinement of an ecological risk assessment, with vulnerability of species to climate change being assessed following the Intergovernmental Panel for Climate Change [48] which determines vulnerability as a function of species exposure to changing environmental variables and their sensitivity to environmental change.…”

“…There is only one other rapid vulnerability assessment study suitable for comparative purposes; other studies examined very different species from temperate habitats. Albeit using a far wider suite of exposure factors, [36] scored S. ghobban as low vulnerability in the Pacific islands but conceded that their approach of assigning medium sensitivity scores when information was uncertain/lacking could have led to misleadingly low vulnerability scores for their coral reef fishes. Of the other four species common to our two studies, we concurred with low vulnerability for yellowfin tuna Thunnus albacares, while the two deep-water snappers, Pristipomoides filamentosus and Etelis carbunculus, which we had scored medium and low respectively, were scored the opposite by [36]; the estuarine crab Scylla serrata they considered low compared to our medium score.…”

“…This formed the basis for subsequent assessments which also included a climate exposure component, with the rationale that the product of a species' sensitivity and its exposure to climate change provides a measure of its vulnerability [29,[32][33][34][35]. Notably, until the recent effort by [36] in the Pacific, assessments have hitherto been conducted on species from cool-and warm-temperate regions, and, apart from [37] in South Africa, we are not aware of any such rapid assessments that have been undertaken for marine fisheries species in Africa or the western Indian Ocean.…”

The land and sea routes to 2030: a call for greater attention on all small islands in global environmental policy

“…These impacts are all compounded by climate change, which disrupts and constricts species' ranges and distributions 17 . Climate change also causes decreases in sea oxygen concentration, rises in sea surface temperature, and increases in ocean acidification that affect marine biodiversity 18 . Extreme events like tropical cyclones and their associated hazards such as storm surges affect not only people and assets, but also species and ecosystems that support livelihoods, services and products that billions of people depend on 19 .…”