Trailing edges projected to move faster than leading edges for large pelagic fish habitats under climate change

Abstract

Trailing edges projected to move faster than leading edges for large pelagic fish habitats under climate change, Deep-Sea Research II, http://dx. doi.org/10. 1016/j.dsr2.2014.04.007 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting galley proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. rates of movement in species habitats. We compared projected shifts in the core habitat of 37 nine large pelagic fish species (five tuna, two billfish and two shark species) off the east coast 38 of Australia at different spatial points (centre, leading and trailing edges of the core habitat), 39 during different seasons (summer and winter), in the near- (2030) will shift faster than the trailing edge, but there are few projections or observations in large 51 pelagic fish to validate this assumption. We found that projected shifts at the trailing edge 52were greater than at the centre and leading of core habitats in all large pelagic fish included in 53 our study. Faster shifts at species trailing edges were due to weaker spatial gradients in 54 temperature in the north than in the south of the study region, in conjunction with relatively 55 constant rates of warming across latitudes. Rather than assuming that leading edges will 56 always move faster, this study suggests that spatial gradients of temperature could be 57 important in determining differences in shifts at different points in species core habitat. 58 59Running title: trailing edges speed up for pelagic fishes 60 61 62 3

Dynamic habitat suitability modelling reveals rapid poleward distribution shift in a mobile apex predator

“…The velocity of the poleward distribution shift reported here for the period 1998-2013, based on empirical observations and multiple environmental factors, is considerably faster than predictions made for similar mobile pelagic predators using modelled climate scenarios ranging from 2030 to 2100 (Hobday, 2010;Robinson et al, 2014). Suitable habitat is shifting south at a mean rate of 88.2 km decade À1 , independent of considerable variation observed due to season and ENSO.…”

“…Despite their widespread distributions, mobile pelagic predators have declined in abundance due to overfishing (Baum & Worm, 2009), causing changes to open ocean food webs (Myers et al, 2007;Worm & Tittensor, 2011). Climate-induced distribution shifts are likely to alter the functioning of pelagic ecosystems already under pressure from anthropogenic stressors (Hsieh et al, 2006;Beaugrand et al, 2008;Hazen et al, 2012;Robinson et al, 2014). Furthermore, mobile pelagic predators represent 20% of total economic value in global marine capture fisheries (FAO, 2012).…”

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Potential impact of climate change on the Intra-Americas Sea: Part 2. Implications for Atlantic bluefin tuna and skipjack tuna adult and larval habitats

“…For example, Dueri et al (2014) predicted an expansion of unsuitable habitat for SKJ in the equatorial Pacific under climate change, with surface temperatures of N31°C considered unsuitable. Robinson et al (2014) assumed a thermal maximum for SKJ of 30°C, and also showed poleward shifts in habitat suitability off southeastern Australia. In contrast, results from this study suggest a general expansion of habitat for SKJ in the GoM and CBN.…”