We deployed jaws of the common thresher shark (Alopias vulpinus) on the seafloor at ~1000 m depth off Monterey California for 8 months. The jaws disintegrated, with all the hyaline cartilage disappearing, leaving some fragments of tessellated cartilage and the teeth. Two different Osedax species, O. packardorum and O. talkovici were found to have bored into the roots of some of the teeth, and were using the dentin pulp, which is rich in collagen, as a food source. The enameloid crowns of the shark teeth and the tessellated cartilage showed no signs of Osedax activity. This is the first demonstration of Osedax exploiting a source of food that is not bone. This raises questions as to the original food source of Osedax ‘bone worms'. Examination for the presence of Osedax in the skeletons and teeth of Mesozoic and possibly even Palaeozoic fossil sharks, bony fish and reptiles is warranted.

The diet and feeding of juvenile common two-banded sea bream, Diplodus vulgaris, in the eastern central Adriatic Sea was studied to better understand local ecosystem dynamics in this region. Stomach contents of 140 individuals with total length (TL) between 22 and 106 mm, collected by small beach seines from February to November, were analysed. Food items identified in stomachs belonged to 16 prey groups: Copepoda, Gastropoda, Teleost eggs, Ostracoda, Polychaeta, Bivalvia, unidentified Crustacea, Amphipoda, Decapoda, Cumacea, Echinoidea, Anisopoda, Euphausiacea, Mysidacea, Branchiopoda and Isopoda. Overall, planktonic copepod crustaceans were the most important prey group (percentage index of relative importance, %IRI = 78.9), followed by gastropods (%IRI = 14.9). All other prey groups had much lower %IRI values and thus were of less importance. Fish size was an important factor influencing food composition. Planktonic copepods were the most important prey in juveniles of smaller sizes (up to 76 mm TL), whereas large-sized juvenile individuals (>76 mm TL) mainly consumed benthic prey, such as gastropods, polychaetes and bivalves. Feeding intensity was very high as indicated by the low vacuity index.

Drawing from ethnographic participation in a ski excursion among a group of Arctic Nature Guide students on the Arctic archipelago of Svalbard, this paper explores guiding as a model of practice embedded in relations – material encounters, discursive frictions and collaborative efforts. The article pays attention to practical negotiations and navigations of these relations while making use of historical scholarship on the role of the guide as a basis for theoretical reflections on the role’s mediation activities. More precisely, the paper advocates a “creation-model of mediation” that challenges modernist representational discourse (and conceptualisations of nature) through a recognition of guiding as productive behaviour. Displaying agency in meaning-making and embodying Svalbard’s transient cosmopolitan population, the guide emerges as a figure on ground far from fixed and settled, and as a tool with which to appraise Svalbard as more geo-aesthetical condition than bounded place.

Since the 1980s, the existence of one or more extinction events in the late Ediacaran has been the subject of debate. Discussion surrounding these events has intensified in the last decade, in concert with efforts to understand drivers of global change over the Ediacaran–Cambrian transition and the appearance of the more modern-looking Phanerozoic biosphere. In this paper we review the history of thought and work surrounding late Ediacaran extinctions, with a particular focus on the last 5 years of paleontological, geochemical, and geochronological research. We consider the extent to which key questions have been answered, and pose new questions which will help to characterize drivers of environmental and biotic change. A key challenge for future work will be the calculation of extinction intensities that account for limited sampling, the duration of Ediacaran ‘assemblage’ zones, and the preponderance of taxa restricted to a single ‘assemblage’; without these data, the extent to which Ediacaran bioevents represent genuine mass extinctions comparable to the ‘Big 5’ extinctions of the Phanerozoic remains to be rigorously tested. Lastly, we propose a revised model for drivers of late Ediacaran extinction pulses that builds off recent data and growing consensus within the field. This model is speculative, but does frame testable hypotheses that can be targeted in the next decade of work.

This review article positions water front-and-center as a key enabler of water–energy–food (WEF) nexus systems. It demonstrates the critical role of water in human civilization, progress, and development, including how water is central to the achievement of many of the United Nations’ sustainable development goals. It is suggested that water may in fact be the most important resource needed in a broader WEF nexus context, as well as in the broader scope of human development. The review shows the consequences of ‘water going wrong’ – when there is too much or too little, and the global impacts of increasing frequency of such events, largely due to an ever more ‘hyperconnected’ world. The review concludes by urging greater ‘nexus awareness’ and systems thinking, especially in policy and decision-making, while cautioning against the potentially ironic situation of returning to a sectoral, water-centric view of resources management.

There is serious concern for the future of a wide range of birds in Java and elsewhere in Indonesia due to both loss of habitat and trapping for the cagebird trade (the so-called “Asian Songbird Crisis”). Despite this concern, few data on presence and abundance of key species exist. We provide such data on 184 bird species from over two years of biodiversity surveys from 37 sites on 12 mountains in West and Central Java. Many of these species are heavily traded, endemic, and globally threatened. Several of the threatened endemics, notably Javan Trogon and Javan Cochoa, were often recorded, in terms of both geographical spread and numerical abundance. Rufous-fronted Laughingthrush, Spotted Crocias, and Orange-spotted Bulbul, believed to be threatened by trapping for the songbird trade, appear to remain fairly widespread. By contrast, Brown-cheeked Bulbul, Chestnut-backed (Javan) Scimitar-babbler, Javan Oriole, and especially Javan Blue-flycatcher, recorded on just a single occasion, and Javan Green Magpie, which we failed to record with certainty, now appear to be extremely rare. Our encounter rates, while not pinned to specific mountains for security reasons, represent an important baseline against which future changes in abundance can be gauged.

Information about population sizes, trends, and habitat use is key for species conservation and management. The Buff-breasted Sandpiper Calidris subruficollis (BBSA) is a long-distance migratory shorebird that breeds in the Arctic and migrates to south-eastern South America, wintering in the grasslands of southern Brazil, Uruguay, and Argentina. Most studies of Nearctic migratory species occur in the Northern Hemisphere, but monitoring these species at non-breeding areas is crucial for conservation during this phase of the annual cycle. Our first objective was to estimate trends of BBSA at four key areas in southern Brazil during the non-breeding season. We surveyed for BBSA and measured vegetation height in most years from 2008/09 to 2019/20. We used hierarchical distance sampling models in which BBSA abundance and density were modelled as a function of vegetation height and corrected for detectability. Next, we used on-the-ground surveys combined with satellite imagery and habitat classification models to estimate BBSA population size in 2019/20 at two major non-breeding areas. We found that abundance and density were negatively affected by increasing vegetation height. Abundance fluctuated five- to eight-fold over the study period, with peaks in the middle of the study (2014/15). We estimated the BBSA wintering population size as 1,201 (95% credible interval [CI]: 637–1,946) birds in Torotama Island and 2,232 (95% CI: 1,199–3,584) in Lagoa do Peixe National Park during the 2019/20 austral summer. Although no pronounced trend was detected, BBSA abundance fluctuated greatly from year to year. Our results demonstrate that only two of the four key areas hold high densities of BBSA and highlight the positive effect of short grass on BBSA numbers. Short-grass coastal habitats used by BBSA are strongly influenced by livestock grazing and climate, and are expected to shrink in size with future development and climatic changes.

Based on censuses in 2021 and 2022 of Bristle-thighed Curlews Numenius tahitiensis on 10 atolls of French Polynesia, the species has declined by c.50% over the last two decades. While the species has recently been down-listed from “Vulnerable” to “Near Threatened”, these new data would qualify it for an “Endangered” Red List status. The non-breeding population on Tuamotu numbers approximately 1,000 curlews and up to 1,500 individuals in all of Eastern Polynesia. On uninhabited islands, the expansion of copra (coconut pulp) exploitation has caused long-term disturbance for curlews, increased predation by pet dogs, and introduced or reinforced non-native rat populations. Climate change, particularly sea-level rise, will add to changes in land use that shrink the suitable habitat for Bristle-thighed Curlews in French Polynesia. As this study shows, obtaining population trends for species breeding in remote areas may best be achieved through surveys at key non-breeding sites.

This study provides the first record of the beaded sea cucumber Euapta lappa at Madeira Island. A single individual was observed during a nocturnal scuba dive at 17 m depth, presumably feeding. After having its previous northern limit in the North-east Atlantic at the Selvagens Islands, this record expands the known distribution and northern limit of this tropical species by about 300 km. This new record of yet another tropical species expanding its range northwards can be seen as another indication of the ongoing tropicalization in the marine environment of Macaronesia in the North-east Atlantic.

Beaks are one of the most important sclerochronological structures used to study the age and growth of cephalopods, in particular Octopus vulgaris Cuvier, 1797. The present study provides results of ageing of 128 O. vulgaris (56–239 mm dorsal mantle length, DML; 121–5974 g total weight, TW) collected in the southern Moroccan Mediterranean coasts between Fnideq and Jebha. The number of increments corresponding to the age (days since hatching) varied from 137–368 in females and from 129–382 in males. There was a significant correlation between beak and somatic growth. The correlation coefficients of the growth curves DML-Age and TW-Age were similar for both power and exponential models: DML = 0.185Age1.188 (R2 = 0.547), DML = 35.933e0.005Age (R2 = 0.546), TW = 0.00002Age3.260 (R2 = 0.532), TW = 29.56e0.014Age (R2 = 0.541). The average width of the increments was similar between females and males. It varied significantly with season and stage of sexual maturity. Comparison of the growth curve with those estimated by other authors showed that Moroccan Mediterranean O. vulgaris grew faster than that of Sardinia (Italy) and slower than that of the Mauritanian coast.

The Blue-throated Hillstar Oreotrochilus cyanolaemus is a recently described hummingbird endemic to the southern Andes of Ecuador. This “Critically Endangered” species faces multiple conservation problems; thus, acquiring basic ecological information is a key step for guiding sound and integral conservation actions. We performed a series of expeditions throughout the cordillera Chilla-Tioloma-Fierro Urco to gain new data about its ecology, abundance, breeding, and distribution. From November 2019 to March 2020, we surveyed a total of 161.6 km searching for O. cyanolaemus, and gathered data on encounter rates, microhabitats used, and flower resources used. From November 2020 to January 2021 we studied the breeding ecology of the species. Occurrence records of O. cyanolaemus were used to build a species distribution model, based on climatic variables and the normalised difference vegetation index (NDVI). We found that the species is relatively more abundant in the western and central portion of its distribution range. Males were found using more shrubby habitats than females, who used more open habitats. They visited flowers of 11 plant species, with Chuquiraga jussieui and Puya ssp. being the most frequently used flowers. Nests were found in caves and rocky walls, and only one out of three active nests was successful. The distribution model indicated that the species has a potential distribution range of 62.7 km2. This manuscript is the first comprehensive evaluation of the ecological requirements of the species, and the information provided has important potential for use as a conservation guide for the species and its habitats.

The Amathole forest complex is the breeding stronghold of the endemic and vulnerable Cape Parrot Poicephalus robustus, and is also one of only two forest complexes in South Africa formally harvested for timber. The aim of this study was to determine if formal harvesting of indigenous trees, primarily the two yellowwood species Afrocarpus falcatus and Podocarpus latifolius, in 9 of 16 Amathole forests has had any effect on the presence of Cape Parrots and three primary nest-excavating species, as well as on parrot breeding. The study used logging data from the past 25 years (1997–2021) as well as data collected by acoustic recording units over two breeding seasons from 2019 to 2021. Cape Parrots were present in 15 of 16 forests, but breeding calls were identified in only seven forests: five in logged and two in unlogged forests. Fourteen of the forests harboured all three primary excavators: Knysna Woodpecker Campethera notata, Olive Woodpecker Dendropicos griseocephalus, and Red-fronted Tinkerbird Pogoniulus pusillus. The last two species were absent from the adjacent Mount Thomas and Kologha forests, respectively, in which parrots were present, but no breeding calls were recorded. Logging of yellowwoods was not found to affect parrot breeding. However, due to the overlap between preferred parrot breeding sites and preferred trees for harvesting, we recommend that harvesting in the five harvested forest blocks where parrot breeding occurs be limited to tree falls, with no standing dead, dying, or damaged trees harvested, to ensure that potential nesting trees are not harvested.

Of the 21 species recorded from the greater Azores region during the HMS ‘Challenger’ Expedition, 12 were newly introduced during the late 19th century. The respective types of these species are fixed, and eight species are redescribed based on scanning electron microscope analysis (Notoplites bilobus, Raxifabia minuta, Hemicyclopora canalifera, Smittoidea oratavensis comb. nov., Buskea ovalis comb. nov., Buskea fayalensis comb. nov., Celleporina ansata comb. nov. and Reteporella atlantica comb. nov.). Another four species are merely dealt with shortly either because the material is insufficiently preserved for a thorough revision (Columnella gracilis, Carbasea pedunculata), or because the species have recently been revised already (Notoplites clausus, Microporella hastigera). Moreover, two Azorean species that were introduced by later workers are synonymized with ‘Challenger’ species: S. oratavensis is considered a senior synonym of Smittia ensifera, and Lekythopora laciniosa is synonymized with C. ansata.