Improving the interpretability of climate landscape metrics: An ecological risk analysis of Japan's Marine Protected Areas

Abstract

Conservation efforts strive to protect significant swaths of terrestrial, freshwater and marine ecosystems from a range of threats. As climate change becomes an increasing concern, these efforts must take into account how resilient-protected spaces will be in the face of future drivers of change such as warming temperatures. Climate landscape metrics, which signal the spatial magnitude and direction of climate change, support a convenient initial assessment of potential threats to and opportunities within ecosystems to inform conservation and policy efforts where biological data are not available. However, inference of risk from purely physical climatic changes is difficult unless set in a meaningful ecological context. Here, we aim to establish this context using historical climatic variability, as a proxy for local adaptation by resident biota, to identify areas where current local climate conditions will remain extant and future regional climate analogues will emerge. This information is then related to the processes governing species' climate-driven range edge dynamics, differentiating changes in local climate conditions as promoters of species range contractions from those in neighbouring locations facilitating range expansions. We applied this approach to assess the future climatic stability and connectivity of Japanese waters and its network of marine protected areas (MPAs). We find 88% of Japanese waters transitioning to climates outside their historical variability bounds by 2035, resulting in large reductions in the amount of available climatic space potentially promoting widespread range contractions and expansions. Areas of high connectivity, where shifting climates converge, are present along sections of the coast facilitated by the strong latitudinal gradient of the Japanese archipelago and its ocean current system. While these areas overlap significantly with areas currently under significant anthropogenic pressures, they also include much of the MPA network that may provide stepping-stone protection for species that must shift their distribution because of climate change.

Evaluating the impact of accounting for coral cover in large‐scale marine conservation prioritizations

“…Yet such spatially explicit information on reef condition is lacking for much of the marine environment, which necessitates the use of surrogate information such as reef extent or bioregionalizations to make decisions about where to allocate resources (e.g., Fernandes et al, ; Green et al, ; Beger et al, ; Jumin et al, ). Some studies have used threats as a proxy for ecosystem condition (García Molinos et al, ; Linke et al, ; Tallis, Ferdaña, & Gray, ). While this may be feasible at smaller scales, large regional prioritizations most often rely on broadly classified morphological features derived from remotely sensed data, and representation is achieved by specifying proportions of each habitat or substrate type to capture their associated biodiversity (Young & Carr, ).…”

VoCC: An r package for calculating the velocity of climate change and related climatic metrics

“…Constant, single thresholds are often defined for each climate variable; pragmatically selected as small as possible yet avoiding artefacts from excessive precision that would otherwise render all future climates non‐analogues (Hamann et al, ). An alternative, which may provide more ecologically meaningful results (García Molinos, Takao, et al, ), is to use local thresholds defined by reference to the baseline climatic variability at each focal cell. The definition of a climatic analogue then becomes cell‐specific:where is the standard deviation (or any other metric of variability) of variable k at focal cell i over the baseline period t .…”

“…Second, the algorithm used for measuring the distance between the focal cell and its geographically closest analogue needs to be selected (argument distfun), which can be any of the Euclidean (Cartesian coordinate system), geographical (great‐circle), or least‐cost path distances. These options can be used to make the distance‐based velocity more relevant to its application, such as the use of least‐cost distances to account for important factors such as barriers to species dispersal (García Molinos, Takao, et al, ) or avoidance of dissimilar climates (Dobrowski & Parks, ).…”

“…An alternative, which may provide more ecologically meaningful results (García Molinos, Takao, et al, 2017), is to use local thresholds defined by reference to the baseline climatic variability at each focal cell. The definition of a climatic analogue then becomes cell-specific:…”

“…area). Though lacking explicit ecological or biological connotation, they can be readily interpreted in terms of exposure to climatic change (Burrows et al, ; Loarie et al, ) and, with caveats (Dobrowski & Parks, ; García Molinos, Takao, et al, ; Hamann, Roberts, Barber, Carroll, & Nielsen, ), linked to potential biological responses (Burrows et al, ; Ordonez, Williams, & Svenning, ). Among the multiple existing metrics (Garcia et al, ), the velocity of climate change (VoCC), representing the rate of movement of climatic isopleths across a landscape (Loarie et al, ), is one of the most widely used in climate‐change ecology and conservation (Table ; Brito‐Morales et al, ), and referred to in policy documents (IPCC, ; MCCIP, ).…”