Beyond the Four Corners of the Convention: Expanding the Scope of Jurisdiction of Law of the Sea Tribunals

In several recent Awards, Part XV tribunals constituted under the UN Convention on the Law of the Sea have been called upon to decide claims based on rights and obligations that find their source in a treaty, agreement, or otherwise binding instrument other than the Convention itself, or on customary international law. This article considers the extent to which such claims fall properly within the jurisdiction of a Part XV tribunal, either on the basis of the applicable law provision in Article 293(1) of the Convention, or on the basis of provisions of the Convention that make reference to other relevant rights and obligations.     

Modelling species distribution in complex environments: an evaluation of predictive ability and reliability in five shorebird species

Aim  Many wader populations around the world are declining as a consequence of habitat degradation or loss. It is therefore important to identify species-specific habitat demands accurately and to define the important factors explaining species distribution, in order to develop tools that can be used in conservation planning. The aim of this study is to create reliable, functional and ecologically interpretable predictive distribution models for five breeding wader species.
Location  The archipelago of SW Finland in the Baltic Sea.
Methods  We used multivariate adaptive regression splines (MARS) to create single-species and multiresponse distribution models based on 525 study islands and 12 abiotic and biotic environmental variables. Model evaluation was carried out on independent data not used in model building (100 + 116 islands). The models were tested for discrimination with receiver-operating characteristic statistics and for calibration with Millers calibration statistics (MCS).
Results  The single-species models for the turnstone ( Arenaria interpres ), redshank ( Tringa totanus ) and oystercatcher ( Haematopus ostralegus ) showed good predictive abilities, regarding both discrimination and calibration, when evaluated on independent data. The multiresponse models for the less prevalent species, common sandpiper ( Actitis hypoleucos ) and the common ringed plover ( Charadrius hiaticula ) had better discriminative abilities than the single-species models. The most influential predictor overall was occurrence of small larids. Exposure, area of forest and low and flat areas were also important, as well as shore habitats.
Main conclusions  We found that the ability of MARS to fit non-linear and multiresponse models makes it a useful method to quantitatively relate species occurrence to environmental characteristics of a complex environment.     

The contribution of different habitat types to species diversity of Baltic uplift islands

Islands are vulnerable ecosystems worldwide, increasingly exposed to human pressure, global climate change and invasive species. Thus, understanding island species diversity is key for nature conservation. Recent studies on insular plant communities indicated that habitat-specific species composition and richness might largely affect diversity patterns observed at the island scale. In consequence, habitat-based approaches are needed to (i) estimate how environmental changes at the habitat scale may affect island diversity, and to (ii) estimate the contribution of different patches of the same habitat to island diversity with respect to habitat-specific environmental constraints.In the present study, we tested these habitat-to-island diversity relationships for shoreline habitats (brackish reeds, salt marsh, rocky shore, tall herbs) and island interior habitats (rocks, semi-natural grassland, pioneer forest, coniferous forest, mixed forest) using 108 islands of three Baltic archipelagos in Sweden. These islands differed in terms of island-scale variables describing effects of island configuration and distance, and habitat-scale variables representing the effects of habitat area, abiotic environment and land-use.The studied habitats differed in their contribution to island species diversity, called habitat specificity. Shoreline habitats shared many common specialist species adapted to extreme conditions like sea salt or bird grazing, while habitats of the island interior harbored mainly species adapted to the specific conditions of a single habitat. We found high variability in habitat specificity as a consequence of habitat-specific environmental factors. Variability was highest for grasslands, where it was related to abandonment and soil fertility, stressing the importance of grassland management for maintaining island biodiversity. Habitats with high habitat specificity through either high species richness or many habitat-specific specialists should be the primary targets for biodiversity management.     

Icelinus pietschi sp. nov. and a rare species, Sigmistes smithi, from the southern Kuril Archipelago (Scorpaeniformes: Cottidae)

A new cottid, Icelinus pietschi sp. nov., and a rare species, Sigmistes smithi Schultz, were collected from intertidal zones in the southern Kuril Archipelago. Icelinus pietschi, represented by five specimens (34.8–42.2 mm SL) from Iturup Island, is distinguished from other species of Icelinus by having the dorsal scale rows terminating before the posteriormost base of the second dorsal fin, spines absent on the dorsal surface of the head, a single common opening of the terminal pores of the mandibular canal, a cirrus on the base of the nasal spine, and a slightly bifid uppermost preopercular spine without denticles dorsally. Six examples (36.8–42.9 mm SL) from Urup Island of Sigmistes smithi, previously known only rarely from the middle of the Aleutian Archipelago, constitute the first record of the species from the western North Pacific. Received: September 26, 1999 / Revised: May 25, 2000 / Accepted: August 29, 2000     

Deep phylogeographic splits and limited mixing by sea surface currents govern genetic population structure in the mangrove genus Lumnitzera (Combretaceae) across the Indonesian Archipelago

The Indonesian Archipelago accommodates the largest mangrove area in Southeast Asia and possesses the world's richest composition of mangrove species. The archipelago comprises areas of the biogeographic regions Sunda and Wallacea, separated by Wallace's line. Here, we used the true mangrove species Lumnitzera littorea and Lumnitzera racemosa as a study case for understanding the effects of phylogeographic history, sea surface currents, and geographical distance on genetic diversity and genetic structure. We sampled 14 populations of L. littorea (N = 106) and 21 populations of L. racemosa (N = 152) from Indonesia and used 3122 and 3048 SNP loci, respectively, genotyped using the ddRADseq approach. We assessed genetic diversity, genetic structure, and effective dispersal of the populations and related them to geographical distance and sea surface currents. Our study revealed low levels of genetic variation at the population level in Lumnitzera. Pronounced genetic differentiation between populations indicated two phylogroups in both species. While in L. littorea the two phylogroups were largely separated by Wallace's line, L. racemosa showed a northwest vs. southeast pattern with strong mixture in Wallacea. Our findings provide novel insights into the phylogeography of the mangrove genus Lumnitzera and the role of sea surface currents in the Indonesian Archipelago.