Jeff A. Eble

Defining Boundaries for Ecosystem-Based Management: A Multispecies Case Study of Marine Connectivity across the Hawaiian Archipelago.

Determining the geographic scale at which to apply ecosystem-based management (EBM) has proven to be an obstacle for many marine conservation programs. Generalizations based on geographic proximity, taxonomy, or life history characteristics provide little predictive power in determining overall patterns of connectivity, and therefore offer little in terms of delineating boundaries for marine spatial management areas. Here, we provide a case study of 27 taxonomically and ecologically diverse species (including reef fishes, marine mammals, gastropods, echinoderms, cnidarians, crustaceans, and an elasmobranch) that reveal four concordant barriers to dispersal within the Hawaiian Archipelago which are not detected in single-species exemplar studies. We contend that this multispecies approach to determine concordant patterns of connectivity is an objective and logical way in which to define the minimum number of management units and that EBM in the Hawaiian Archipelago requires at least five spatially managed regions.

Dramatic response to climate change in the Southwest: Robert Whittaker's 1963 Arizona Mountain plant transect revisited

Models analyzing how Southwestern plant communities will respond to climate change predict that increases in temperature will lead to upward elevational shifts of montane species. We tested this hypothesis by reexamining Robert Whittakers 1963 plant transect in the Santa Catalina Mountains of southern Arizona, finding that this process is already well underway. Our survey, five decades after Whittakers, reveals large changes in the elevational ranges of common montane plants, while mean annual rainfall has decreased over the past 20 years, and mean annual temperatures increased 0.25°C/decade from 1949 to 2011 in the Tucson Basin. Although elevational changes in species are individualistic, significant overall upward movement of the lower elevation boundaries, and elevational range contractions, have occurred. This is the first documentation of significant upward shifts of lower elevation range boundaries in Southwestern montane plant species over decadal time, confirming that previous hypotheses are correct in their prediction that mountain communities in the Southwest will be strongly impacted by warming, and that the Southwest is already experiencing a rapid vegetation change.

Not All Larvae Stay Close to Home: Insights into Marine Population Connectivity with a Focus on the Brown Surgeonfish (Acanthurus nigrofuscus).

Recent reports of localized larval recruitment in predominately small-range fishes are countered by studies that show high genetic connectivity across large oceanic distances. This discrepancy may result from the different timescales over which genetic and demographic processes operate or rather may indicate regular long-distance dispersal in some species. Here, we contribute an analysis of mtDNA cytochrome b diversity in the widely distributed Brown Surgeonfish (Acanthurus nigrofuscus; N = 560), which revealed significant genetic structure only at the extremes of the range (ΦCT = 0.452; P < .001). Collections from Hawaii to the Eastern Indian Ocean comprise one large, undifferentiated population. This pattern of limited genetic subdivision across reefs of the central Indo-Pacific has been observed in a number of large-range reef fishes. Conversely, small-range fishes are often deeply structured over the same area. These findings demonstrate population connectivity differences among species at biogeographic and evolutionary timescales, which likely translates into differences in dispersal ability at ecological and demographic timescales. While interspecific differences in population connectivity complicate the design of management strategies, the integration of multiscale connectivity patterns into marine resource planning will help ensure long-term ecosystem stability by preserving functionally diverse communities.

British Indian ocean territory (the Chagos archipelago) : setting, connections and the marine protected area

The British Indian Ocean Territory consists of the Chagos archipelago, almost all of which was designated a no-take MPA in 2010. It covers 650,000 km2, with >60,000 km2 shallow limestone platform and reefs. This has doubled the global cover of such MPAs. It has strong biological affinities with the western Indian Ocean, and larval travel time to reefs to the west of it is 25–35 days. Genetic work is only recently commencing, but it is likely to be a cross-roads, or bridge, in this respect. A licensed fishery used to exist, but this too was closed in 2010, and the large diameter of the area may prove to be a significant reserve for pelagic fishes such as tuna also. The region probably contains about 300 sea mounts and knolls, which is about 10 % of all Indian Ocean seamounts and nearly half of all those protected worldwide, and so the area is regionally important for these features as well with their unexplored but probably diverse deep benthic and fish biota. The area is also well placed to fill a large gap in global monitoring systems; it is located in key region of climate variability, so programmes carried out there are particularly important to research into climate change effects also. The area has very high conservation value and is an important biological asset in an ocean where most reefs show significant and continuing decline in health.