Reproductive and sexual characteristics in five Lethrinus species in waters off the Ryukyu Islands

Gonads of five lethrinids, viz., Lethrinus harak, L. miniatus, L. obsoletus, L. ornatus, and L. sp. 2, were collected monthly in waters off the Ryukyu Islands and observed histologically to reveal their spawning periods and size at sexual maturation and sexual transition. The spawning period was from April to November for L. harak, from April to July for L. miniatus, from April to October for L. obsoletus, from May to November for L. ornatus, and from April to October for L. sp. 2. Sexual patterns in the five species were determined by fork length at both sexual maturation and sexual transition. The body size (fork length, FL) and sex ratio (% of female) at 90% maturity in L. harak were 21.1 cm FL and 90%, respectively; those of L. miniatus were 42.2 cm FL and 80%; 25.7 cm FL and 60% for L. obsoletus; about 20 cm FL and 90% for L. ornatus; and about 26 cm FL and 90% for L. sp. 2. Because the sex ratios decreased to 0% at the maximum size classes in L. miniatus, L. ornatus, and L. sp. 2, the sexual patterns in these species were considered to be protogynous hermaphrodite. Although the sex ratio (% of female) once decreased to about 30% at 28 cm FL, rapid increase occurred in the larger size class in L. harak. However, the increase did not result from sexual transition. Hence, the sexual pattern of L. harak was considered to be protogynous hermaphrodite. Because the sex ratio (% of female) at body sizes larger than 23 cm FL was stable at about 60% in L. obsoletus, the sexual pattern was determined to be one of juvenile hermaphrodites.     

Multi Year Observations Reveal Variability in Residence of a Tropical Demersal Fish,Lethrinus nebulosus: Implications for Spatial Management

Off the Ningaloo coast of North West Western Australia, Spangled Emperor Lethrinus nebulosus are among the most highly targeted recreational fish species. The Ningaloo Reef Marine Park comprises an area of 4,566 km² of which 34% is protected from fishing by 18 no-take sanctuary zones ranging in size from 0.08–44.8 km². To better understand Spangled Emperor movements and the adequacy of sanctuary zones within the Ningaloo Reef Marine Park for this species, 84 Spangled Emperor of a broad spectrum of maturity and sex were tagged using internal acoustic tags in a range of lagoon and reef slope habitats both inside and adjacent to the Mangrove Bay Sanctuary zone. Kernel Utilisation Distribution (KUD) was calculated for 39 resident individuals that were detected for more than 30 days. There was no relationship with fish size and movement or site fidelity. Average home range (95% KUD) for residents was 8.5±0.5 km² compared to average sanctuary zone size of 30 km². Calculated home range was stable over time resulting in resident animals tagged inside the sanctuary zone spending ∼80% of time within the sanctuary boundaries. The number of fish remaining within the array of receivers declined steadily over time and after one year more than 60% of tagged fish had moved outside the sanctuary zone and also beyond the 28 km² array of receivers. Long term monitoring identified the importance of shifting home range and was essential for understanding overall residency within protected areas and also for identifying spawning related movements. This study indicates that despite exhibiting stable and small home ranges over periods of one to two years, more than half the population of spangled emperor move at scales greater than average sanctuary size within the Ningaloo Reef Marine Park.     

The Mangrove Nursery Paradigm Revisited: Otolith Stable Isotopes Support Nursery-to-Reef Movements by Indo-Pacific Fishes

Mangroves and seagrass beds have long been perceived as important nurseries for many fish species. While there is growing evidence from the Western Atlantic that mangrove habitats are intricately connected to coral reefs through ontogenetic fish migrations, there is an ongoing debate of the value of these coastal ecosystems in the Indo-Pacific. The present study used natural tags, viz. otolith stable carbon and oxygen isotopes, to investigate for the first time the degree to which multiple tropical juvenile habitats subsidize coral reef fish populations in the Indo Pacific (Tanzania). Otoliths of three reef fish species (Lethrinus harak, L. lentjan and Lutjanus fulviflamma) were collected in mangrove, seagrass and coral reef habitats and analyzed for stable isotope ratios in the juvenile and adult otolith zones. δ¹³C signatures were significantly depleted in the juvenile compared to the adult zones, indicative of different habitat use through ontogeny. Maximum likelihood analysis identified that 82% of adult reef L. harak had resided in either mangrove (29%) or seagrass (53%) or reef (18%) habitats as juveniles. Of adult L. fulviflamma caught from offshore reefs, 99% had passed through mangroves habitats as juveniles. In contrast, L. lentjan adults originated predominantly from coral reefs (65–72%) as opposed to inshore vegetated habitats (28–35%). This study presents conclusive evidence for a nursery role of Indo-Pacific mangrove habitats for reef fish populations. It shows that intertidal habitats that are only temporarily available can form an important juvenile habitat for some species, and that reef fish populations are often replenished by multiple coastal habitats. Maintaining connectivity between inshore vegetated habitats and coral reefs, and conserving habitat mosaics rather than single nursery habitats, is a major priority for the sustainability of various Indo Pacific fish populations.     

Life history of the orange-striped emperor <Emphasis Type="Italic">Lethrinus obsoletus</Emphasis> from the Mariana Islands

The present study investigated the age-based demography of the orange-striped emperor, Lethrinus obsoletus, from commercial samples in the Commonwealth of the Northern Mariana Islands (CNMI), spanning a 24-month market sampling period. Information on growth, life span, mortality, and reproduction was derived through analysis of sectioned sagittal otoliths and gonad material. The species had a moderate longevity of 13 years while females and males reached 50% sexual maturity at 3.8 years (22.9 cm fork length) and 2.8 years (19.9 cm fork length), respectively. Histological examination of gonads and sex-specific age frequency distributions suggest the sexual ontogeny of the species conforms to juvenile hermaphroditism, whereby sexual transition from female to male occurred prior to maturation. No annual spawning periods were identified, but the ubiquitous presence of post-ovulatory follicles in females and spermatogenic material in males coupled with a consistent lunar trend in gonadosomatic index patterns suggests the species spawns every lunar cycle throughout the year with spawning activity potentially increasing around the new moon. Ratios of natural to fishing mortality indicate a moderate level of exploitation (0.37); however, a large portion of harvested females had not reached reproductive maturity, suggesting that formal assessments of stock status are warranted to ensure the sustainable harvest of the species in CNMI.     

Marine reserves and reproductive biomass: a case study of a heavily targeted reef fish

Recruitment overfishing (the reduction of a spawning stock past a point at which the stock can no longer replenish itself) is a common problem which can lead to a rapid and irreversible fishery collapse. Averting this disaster requires maintaining a sufficient spawning population to buffer stochastic fluctuations in recruitment of heavily harvested stocks. Optimal strategies for managing spawner biomass are well developed for temperate systems, yet remain uncertain for tropical fisheries, where the danger of collapse from recruitment overfishing looms largest. In this study, we explored empirically and through modeling, the role of marine reserves in maximizing spawner biomass of a heavily exploited reef fish, Lethrinus harak around Guam, Micronesia. On average, spawner biomass was 16 times higher inside the reserves compared with adjacent fished sites. Adult density and habitat-specific mean fish size were also significantly greater. We used these data in an age-structured population model to explore the effect of several management scenarios on L. harak demography. Under minimum-size limits, unlimited extraction and all rotational-closure scenarios, the model predicts that preferential mortality of larger and older fish prompt dramatic declines in spawner biomass and the proportion of male fish, as well as considerable declines in total abundance. For rotational closures this occurred because of the mismatch between the scales of recovery and extraction. Our results highlight how alternative management scenarios fall short in comparison to marine reserves in preserving reproductively viable fish populations on coral reefs.     

Comparative biology of tropical Lethrinus species (Lethrinidae): challenges for multi‐species management

Life‐history characteristics of six tropical Lethrinus species sampled from the Great Barrier Reef World Heritage Area were compared. Two species groups were identified based on fork length (L_F): large species with maximum L_F > 640 mm (longface emperor Lethrinus olivaceus, yellowlip emperor Lethrinus xanthochilus and spangled emperor Lethrinus nebulosus) and small species with maximum L_F < 480 mm (Pacific yellowtail emperor Lethrinus atkinsoni, pink ear emperor Lethrinus lentjan and ornate emperor Lethrinus ornatus). Lifespan was not correlated with L_F. Early growth for all species was rapid and similar during the first few years of life, but coefficients of the von Bertalanffy growth function varied considerably among species. Growth also differed between sexes for L. atkinsoni. Reproductive characteristics varied among species, with peak periods of spawning occurring in November to December for L. atkinsoni, July to August for L. nebulous, September to October for L. olivaceus and a protracted season for L. lentjan, although fewer samples were available for the last two species. Sex‐specific L_F and age distributions and gonad histology of L. lentjan were suggestive of a functional protogynous reproductive pattern, as observed in other lethrinids. Gonad histology indicated non‐functional protogynous hermaphroditism for L. atkinsoni and L. nebulosus. The diversity of life histories among these closely related species emphasizes the difficulty in devising single management strategies appropriate for multi‐species fisheries and illustrates the importance of understanding species‐specific life histories to infer responses to exploitation.     

Home range behaviour of the monogamous Australian seahorse, <Emphasis Type="Italic">Hippocampus whitei</Emphasis>

We provide a quantitative account of local movements in the monogamous Australian species Hippocampus whitei, as a rare report of home range size in fishes living in seagrass habitats. Our study took place in shallow Posidonia seagrass beds in Port Jackson (Sydney Harbour), principally during January to March. Daily monitoring of individual seahorses during underwater observations revealed that both sexes maintained small and apparently undefended home ranges for several breeding cycles at least. Female home ranges were significantly larger than males, when analysed by both the minimum convex polygon and grid cell methods. Home range size was not correlated with either body size or seahorse density. Presumably, home ranges were small in H. whitei because camouflage (to avoid predation and to capture prey), mate fidelity and parental brooding meant they accrued little benefit (and potentially considerable cost) from moving more extensively. Sex differences in home range size may arise from constraints associated with male pregnancy. These fish are among the most sedentary of vertebrates, with relatively small home ranges equalled only by coral reef species. In terms of their conservation, relatively small protected areas may be sufficient to support breeding populations of H. whitei although that limited movement may result in considerable delays in the recolonisation of depleted areas.     

Larval dispersal and movement patterns of coral reef fishes,and implications for marine reserve network design

Well‐designed and effectively managed networks of marine reserves can be effective tools for both fisheries management and biodiversity conservation. Connectivity, the demographic linking of local populations through the dispersal of individuals as larvae, juveniles or adults, is a key ecological factor to consider in marine reserve design, since it has important implications for the persistence of metapopulations and their recovery from disturbance. For marine reserves to protect biodiversity and enhance populations of species in fished areas, they must be able to sustain focal species (particularly fishery species) within their boundaries, and be spaced such that they can function as mutually replenishing networks whilst providing recruitment subsidies to fished areas. Thus the configuration (size, spacing and location) of individual reserves within a network should be informed by larval dispersal and movement patterns of the species for which protection is required. In the past, empirical data regarding larval dispersal and movement patterns of adults and juveniles of many tropical marine species have been unavailable or inaccessible to practitioners responsible for marine reserve design. Recent empirical studies using new technologies have also provided fresh insights into movement patterns of many species and redefined our understanding of connectivity among populations through larval dispersal. Our review of movement patterns of 34 families (210 species) of coral reef fishes demonstrates that movement patterns (home ranges, ontogenetic shifts and spawning migrations) vary among and within species, and are influenced by a range of factors (e.g. size, sex, behaviour, density, habitat characteristics, season, tide and time of day). Some species move <0.1–0.5 km (e.g. damselfishes, butterflyfishes and angelfishes), <0.5–3 km (e.g. most parrotfishes, goatfishes and surgeonfishes) or 3–10 km (e.g. large parrotfishes and wrasses), while others move tens to hundreds (e.g. some groupers, emperors, snappers and jacks) or thousands of kilometres (e.g. some sharks and tuna). Larval dispersal distances tend to be <5–15 km, and self‐recruitment is common. Synthesising this information allows us, for the first time, to provide species, specific advice on the size, spacing and location of marine reserves in tropical marine ecosystems to maximise benefits for conservation and fisheries management for a range of taxa. We recommend that: (i) marine reserves should be more than twice the size of the home range of focal species (in all directions), thus marine reserves of various sizes will be required depending on which species require protection, how far they move, and if other effective protection is in place outside reserves; (ii) reserve spacing should be <15 km, with smaller reserves spaced more closely; and (iii) marine reserves should include habitats that are critical to the life history of focal species (e.g. home ranges, nursery grounds, migration corridors and spawning aggregations), and be located to accommodate movement patterns among these. We also provide practical advice for practitioners on how to use this information to design, evaluate and monitor the effectiveness of marine reserve networks within broader ecological, socioeconomic and management contexts.     

Polygynous Mating System of Trimma okinawae (Pisces: Gobiidae) at Kagoshima,Japan with a Note on Sex Change

Mating system, social structure and reproductive behaviour of the gobiid fish Trimma okinawae were studied at Akamizu, Kagoshima, Japan. Mating system of this species is polygyny. There were two types of habitat-related distribution patterns of male and female home ranges: females have home ranges outside a small territory of the male; female home ranges are covered by male territory. Spawnings take place with a cycle of four to five days during the spawning season of June to Sept. In the morning of the day of spawning, males stay at the spawning sites. Females visit the site and spawn with the male. On days between spawnings males exhibit courtship displays at female home ranges. Higher reproductive success is not connected with frequency of such courting of the male, but with male size. The largest female of a social unit changes into a male when the dominant male is removed, which shows that T. okinawae is a hermaphrodite.     

Cranial morphometrics and mitochondrial DNA sequences distinguish cryptic species of the longface emperor (Lethrinus olivaceus), an emblematic fish of Indo-West Pacific coral reefs

Range-wide morphometric variability (cranial measurements) and genetic variability (nucleotide sequences of the cytochrome b gene) were investigated in the longface emperor, Lethrinus olivaceus (Lethrinidae), an emblematic large predatory fish of Indo-West Pacific coral reefs. Two cranial morphotypes were observed, one present from the Indian Ocean to the Coral Triangle and the other one, from the Coral Triangle to the western Central Pacific. The two morphotypes are concordant with reciprocally monophyletic mitochondrial lineages separated by 9.5% net nucleotide distance. These results suggest an old evolutionary history for L. olivaceus, which consists of two distinct species (Lethrinus sp. A in the Indian Ocean and Coral Triangle, Lethrinus sp. B in the western Pacific Ocean), whose distribution ranges meet or overlap in the eastern part of the Coral Triangle, in Taiwan and in West Papua. Lethrinus sp. A comprises two distinct mitochondrial lineages separated by 1.7% net nucleotide distance, one exclusive to the populations from the Indian Ocean, the other exclusive to Coral Triangle populations. The latter observation might be explained by vicariance, whereby the two lineages have been isolated from one another on either side of the Sunda Shelf because of low sea level in the Pleistocene. To clarify the nomenclature of this species complex, we recommend sequencing a fragment of the cytochrome b gene of the holotypes of L. olivaceus and of its first junior synonyms L. rostratus and L. waigiensis.     

Cryptic species and parallel genetic structuring in Lethrinid fish: Implications for conservation and management in the southwest Indian Ocean

Analysis of genetic variation can provide insights into ecological and evolutionary diversification which, for commercially harvested species, can also be relevant to the implementation of spatial management strategies and sustainability. In comparison with other marine biodiversity hot spots, there has been less genetic research on the fauna of the southwest Indian Ocean (SWIO). This is epitomized by the lack of information for lethrinid fish, which support socioeconomically important fisheries in the region. This study combines comparative phylogeographic and population genetic analyses with ecological niche modeling to investigate historical and contemporary population dynamics of two species of emperor fish (Lethrinus mahsena and Lethrinus harak) across the SWIO. Both species shared similarly shallow phylogeographic patterns and modeled historical (LGM) habitat occupancies. For both species, allele frequency and kinship analyses of microsatellite variation revealed highly significant structure with no clear geographical pattern and nonrandom genetic relatedness among individuals within samples. The genetic patterns for both species indicate recurrent processes within the region that prevent genetic mixing, at least on timescales of interest to fishery managers, and the potential roles of recruitment variability and population isolation are discussed in light of biological and environmental information. This consistency in both historical and recurrent population processes indicates that the use of model species may be valuable in management initiatives with finite resources to predict population structure, at least in cases wherein biogeographic and ecological differences between taxa are minimized. Paradoxically, mtDNA sequencing and microsatellite analysis of samples from the Seychelles revealed a potential cryptic species occurring in sympatry with, and seemingly morphologically identical to, L. mahsena. BLAST results point to the likely misidentification of species and incongruence between voucher specimens, DNA barcodes, and taxonomy within the group, which highlights the utility and necessity of genetic approaches to characterize baseline biodiversity in the region before such model‐based methods are employed.     

Which population density affects home ranges of co-occurring rodents?

Animal space use patterns can be affected by the intra- and interspecific density of individuals competing for resources, with home ranges generally decreasing with increasing population density. By applying spatially explicit capture–recapture models implemented in the R package secr, we study whether home ranges of co-occurring yellow-necked mice, Apodemus flavicollis, and bank voles, Myodes glareolus, are related to population density of (a) conspecifics (intraspecific density), (b) the other sympatric species, A. flavicollis or M. glareolus (interspecific density), or (c) total rodent density (A. flavicollis plus M. glareolus). Home ranges of both species were negatively related to intraspecific population density, and were not related to interspecific density or total rodent density. Given that rodents tend to reduce home ranges if resources are abundant, this pattern may merely result from the higher abundance of resources generally associated with high density populations, if the two species were responding to different subsets of resources. However, intraspecific density could directly reduce home ranges, because conspecifics are more likely to interfere with each other due to the overlapping of space use patterns. Therefore, results suggest complementary space or resource use patterns between species, with consequent weak competition and niche differentiation. Across several years and population densities, home ranges of the two co-occurring rodents thus appear to be affected by conspecifics only, suggesting that the two species may coexist in the study area owing to limited space or resource use overlap.     

Reproductive activity in the checkered snapper, Lutjanus decussatus, off Ishigaki Island, Okinawa

The checkered snapper, Lutjanus decussatus, is an important species for fisheries in the Okinawan region. This study estimated the reproduction of this lutjanid species in the waters around Ishigaki Island. The main spawning season was estimated to be between June and October, since oocytes at the maturation stage and/or postovulatory follicles were found during the study period. In the main spawning season, high gonadosomatic index values were found around the time of the last quarter moon for each month from June to September. It is suggested that L. decussatus is a lunar-synchronized spawner off Ishigaki Island.     

Broadcast Spawning by Pocillopora Species on the Great Barrier Reef

The coral genus Pocillopora is one of the few to include some species that broadcast spawn gametes and some species that brood larvae, although reports of reproductive mode and timing vary within and among species across their range. Notably, the ubiquitous Pocillopora damicornis has been described as both a brooder and spawner, although evidence of broadcast spawning is rare. Here, we report observations of broadcast-spawning in four species of Pocillopora on the Great Barrier Reef (GBR), including P. damicornis. All species spawned predictably during the early morning, two days following the full moon, and spawning was observed in multiple months over the summer period (November to February). Eggs and sperm were free-spawned concurrently. Eggs were negatively buoyant and contained Symbiodinium. This newfound knowledge on the mode, timing and regularity of broadcast spawning in Pocillopora spp. on the GBR brings us one step closer to elucidating the complex reproductive ecology of these species.     

Social system of an inshore stock of the red hind grouper,Epinephelus guttatus (Pisces: Serranidae)

Synopsis According to sex allocation theory, the decision by a female in protogynous fish species to change sex or not should be influenced by, among other things, the mating sex ratio during spawning periods and/or by factors that vary directly with the spawning sex ratio, such as relative rates of behavioral interaction with males and females outside of spawning periods. In groupers that only spawn during a few weeks of the year in large aggregations, individuals must assess the relative value of changing sex or not entirely within the aggregation unless the social system during the remainder of the year provides a behavioral equivalent of the mating sex ratio. Fifty-five individuals of the red hind,Epinephelus guttatus, were tagged and repeatedly located during a 152-day period within a 100 × 100 m grid on a shallow forereef off southwestern Puerto Rico. The home ranges of 22 tagged individuals sighted 10 or more times were 112–5636 m² in area. Individual home ranges overlapped with the home ranges of 1–18 other individuals. Home ranges of small fish were not clustered within the borders of the home range of larger fish, i.e. fish did not form spatially defined social units. At the end of the study, 31 tagged individuals remained on the grid together with five newly sighted fish. All 36 individuals proved on histological examination to be females similar in size to females in the spawning aggregation of the following year. The sex ratio of this all-female inshore stock differed significantly from the sex ratio of that spawning aggregation. Hence, information predicting the reproductive value of a sex change is not available to females in the inshore stock during nonspawning months.     

Long-term investigations of migratory behaviour of asp (Aspius aspius L.) in the middle part of the Elbe River, Germany

The migratory behaviour, habitat use, home range and temporal and spatial variability of migrations of the potamodromous asp (Aspius aspius L.) in the large Elbe River, Germany, were studied in the years 1997–2000. Fifty‐three asp were tagged with surgically implanted radio transmitters and individually hand‐tracked usually once per week for about 1 year; 50% of the asp exclusively inhabited the main channel, 22% moved for short visits into other habitats and 24% changed between winter habitats in a harbour or oxbow and summer habitats in the main channel where they spawned in late March/April. The migratory behaviour of asp was highly variable; 34 asp observed for more than 1 year lived in home ranges of 1 to >100 stream kilometres (skm) mostly near their capture site. Longest observed migration from summer habitat in the Tidal Elbe back to the spawning ground in the Middle Elbe was 166 skm. After the spawning period or the spawning period thereafter, nine of these 34 fish left their home ranges for a long downstream migration without returning during the observation period. From these results we conclude that populations of rheophilic, potamodromous fish use a surprisingly long river section and that weirs have a strong impact on migration patterns and, ultimately, on population dynamics of these species.     

Passive acoustic telemetry reveals highly variable home range and movement patterns among unicornfish within a marine reserve

Marine reserves are the primary management tool for Guam’s reef fish fishery. While a build-up of fish biomass has occurred inside reserve boundaries, it is unknown whether reserve size matches the scale of movement of target species. Using passive acoustic telemetry, we quantified movement patterns and home range size of two heavily exploited unicornfish Naso unicornis and Naso lituratus. Fifteen fish (N. unicornis: n = 7; N. lituratus: n = 4 male, n = 4 female) were fitted with internal acoustic tags and tracked continuously over four months within a remote acoustic receiver array located in a decade-old marine reserve. This approach provided robust estimates of unicornfish movement patterns and home range size. The mean home range of 3.2 ha for N. unicornis was almost ten times larger than that previously recorded from a three-week tracking study of the species in Hawaii. While N. lituratus were smaller in body size, their mean home range (6.8 ha) was over twice that of N. unicornis. Both species displayed strong site fidelity, particularly during nocturnal and crepuscular periods. Although there was some overlap, individual movement patterns and home range size were highly variable within species and between sexes. N. unicornis home range increased with body size, and only the three largest fish home ranges extended into the deeper outer reef slope beyond the shallow reef flat. Both Naso species favoured habitat dominated by corals. Some individuals made predictable daily crepuscular migrations between different locations or habitat types. There was no evidence of significant spillover from the marine reserve into adjacent fished areas. Strong site fidelity coupled with negligible spillover suggests that small-scale reserves, with natural habitat boundaries to emigration, are effective in protecting localized unicornfish populations.     

Temporal variation in habitat use by nekton in a subtropical estuarine system

Utilisation by fish of different estuarine habitats is known to vary at many different temporal scales, however no study to date has examined how utilisation varies at all the relevant times scales simultaneously. Here, we compare the utilisation by fish of sandy, intertidal foreshore habitats in a subtropical estuary at four temporal scales: between major spawning periods (spring/summer and winter), among months within spawning periods, between the full and new moon each month, and between night and day within those lunar phases. Comparisons of assemblage composition, abundance of individuals and of fish in seven different ‘ecological guilds’ were used to identify the temporal scales at which fish varied their use of unvegetated sandy habitats in the lower Noosa Estuary, Queensland, Australia. Fish assemblages were sampled with a seine net at three different regions. The most numerically dominant species caught were southern herring (Herklotsichthys castelnaui: Clupeidae), sand whiting (Sillago ciliata: Sillaginidae), weeping toadfish (Torquigener pleurogramma: Tetraodontidae), and silver biddy (Gerres subfasciatus: Gerreidae). Considerable variation at a range of temporal scales from short term (day versus night) to longer term (spawning periods) was detected for all but one of the variables examined. The clearest patterns were observed for diurnal effects, where generally abundance was greater at night than during the day. There were also strong lunar effects, although there were no consistent patterns between full moon and new moon periods. Significant differences among months within spawning periods were more common than differences between the actual spawning periods. The results clearly indicate that utilisation of sandy, unvegetated estuarine habitats is very dynamic and highly variable in space and time.     

Range,population structure and morphological characterization of the small range endemic bush-cricket <Emphasis Type="Italic">Lluciapomaresius panteli</Emphasis> (Orthoptera: Tettigoniidae: Bradyporinae)

The bush-cricket genus Lluciapomaresius Barat, 2012 is endemic to the Iberian Peninsula. It includes at least seven species, most of which are narrow endemics restricted to single or few mountain ranges across the Peninsula. All of them are currently included under different categories in the IUCN red list. One of the species listed as data deficient is Pantel’s Saddle Bush-cricket L. panteli (Navàs 1899), an iconic species of the Montsant Natural Park. Up to now, it was thought to be restricted to few square kilometres in the Montsant range, in southern Catalonia (north-east Iberian Peninsula). The species was at some point suspected extinct, but it was rediscovered in 2000. More recently, a new species, L. nisae Olmo-Vidal 2017, was described based on specimens found in neighbouring Llaberia range, about 20 km south from Montsant. In this study, we present new data based on a systematic sampling of Lluciapomaresius across known and nearby locations in Montsant, Llaberia and surrounding ranges. The records and collected specimens allow us to provide a better delimitation of the actual distribution range and to conduct a detailed morphological study to shed light on the degree of differentiation of populations in different parts of the range, further supported by DNA sequence data of mitochondrial and nuclear genes. Our results show that L. nisae is a synonym of L. panteli as judged by the small genetic and morphological variability, better interpreted as the result of local differentiation of populations following post-glacial isolation. We further confirm the extremely small ranges and isolation of the Lluciapomaresius populations and propose to move the species towards the EN (endangered) category in the IUCN Red List. Additional research on the still unknown aspects of its biology and ecology is needed to implement reasoned and effective conservation measures that ensure its survival.     

Present patterns and future prospects for biodiversity in the Western Hemisphere

Creating networks of nature reserves to protect areas rich in biodiversity from the adverse impacts of anthropogenic change is a critical and urgent task. We illustrate the skewed geographical and size distributions of protected areas in the Western Hemisphere. For instance, 811 of 1413 reserves in the Western Hemisphere are smaller than 10 km², and 35% of the total area of these reserves is in Alaska. We compile ranges for all bats in the continental Western Hemisphere and find that 82% of threatened and small‐range species are not protected adequately. Many of the most vulnerable species occur in the areas of highest human density. We provide maps delineating areas where conservation investments may have the greatest impact in preventing biodiversity losses.