Island Conservation Society

ABSTRACT Aim Knowledge of the main drivers of population differentiation is crucial for understanding evolutionary processes and preserving biodiversity. While primarily studied in terrestrial habitats, the mechanisms operating in the marine realm are less well understood. This study reconstructed the phylogeographic history of a tropical seabird to identify relevant marine barriers promoting intraspecific diversity in the Western Indian Ocean. Location Western Indian Ocean. Taxon Three subspecies of tropical shearwater : Puffinus bailloni bailloni , P. b. nicolae, P. b. colstoni. Methods We used restriction site‐associated DNA sequencing and applied population genomics to birds from six breeding colonies to assess intraspecific diversity, population genetic structure and connectivity in the tropical shearwater. Results were complemented with data from six oceanographic variables and effective migration surfaces to evaluate the role of oceanographic factors in driving population differentiation. Results All analyses consistently separated the birds from the northern colonies (subsp. nicolae and colstoni ) from those of the southern islands (subsp. bailloni ), but failed to assign the colstoni birds as a different taxon. Results revealed remarkable levels of genetic differentiation within an ocean basin in a highly vagile species and suggested higher levels of gene flow at the northern limit of the species' distribution compared to the southern range. Main Conclusions Our study suggests that ocean surfaces and sea surface temperature may constitute an important barrier to gene flow for the tropical shearwater and potentially other marine species in the region. This study does not support the colstoni form as a different subspecies, highlighting the need for further taxonomic reassessment. Ultimately, the results allowed us to identify Europa and Aldabra as the most threatened management units and propose conservation strategies directly applicable to these most at‐risk colonies.

ObjectiveSheehan's syndrome (SS) is a rare endocrine disorder caused by ischemic necrosis of the anterior pituitary gland secondary to massive postpartum hemorrhage (PPH) and shock. It commonly leads to multiple hormonal deficiencies, such as adrenal insufficiency, hypothyroidism, and hypopituitarism. Affected individuals may present with signs and symptoms including weight gain or loss, cold intolerance, hair loss, menstrual irregularities, and hypotension. Diagnosis is often delayed due to its nonspecific presentation and overlap with conditions like postpartum depression and chronic fatigue syndrome. This case report highlights the clinical presentation, management challenges, and complications associated with the delayed diagnosis of SS.Case PresentationA 35-year-old female was diagnosed with SS in 2016, at the age of 26, following severe PPH and hemorrhagic shock after a vaginal delivery in 2013. Initially, she experienced failure to lactate, followed by amenorrhea, frontal balding, weight loss, hypotension, chronic fatigue, mood swings, and polyuria. For several years, her symptoms were misattributed to postpartum depression, resulting in delayed diagnosis and treatment. A comprehensive endocrine evaluation revealed secondary adrenal insufficiency, central hypothyroidism, and hypogonadotropic hypogonadism, as evidenced by low levels of ACTH, cortisol, TSH, free T4, FSH, LH, and prolactin. Magnetic resonance imaging (MRI) confirmed partial empty sella, supporting the diagnosis of SS. She was started on lifelong hormone replacement therapy (HRT) consisting of hydrocortisone, levothyroxine, and estrogen. She remained highly sensitive to hormone doses, requiring frequent adjustments every other month. Despite modifications, she continued to experience persistent symptoms, including fatigue, hair loss, extreme mood swings, night sweats, and gastrointestinal symptoms such as abdominal discomfort, epigastric pain (worsened on an empty stomach), nausea, vomiting, bloating, and passage of blood in stool, likely related to long-term medication use. Pregnancy was later achieved through ovulation induction using human chorionic gonadotropin (HCG) and human menopausal gonadotropin (HMG). She developed an adrenal crisis during pregnancy, which was managed through hydrocortisone dose modification. The immediate postpartum period was uneventful under treatment, but she required close endocrine follow-up for ongoing metabolic and reproductive concerns.ConclusionThis case highlights the typical clinical presentation of SS in a postpartum patient, including lactation failure, fatigue, and amenorrhea, which can facilitate early diagnosis of this serious and potentially life-threatening condition. Delayed diagnosis is often linked to prolonged morbidity, affecting both quality of life and fertility. Lifelong HRT, regular endocrinological monitoring, and individualized treatment plans are essential for managing endocrine dysfunction, osteoporosis risk, and cardiovascular complications. Awareness, early screening, and multidisciplinary collaboration among endocrinologists, obstetricians, and reproductive specialists are pivotal in improving long-term outcomes and reducing diagnostic delays.

Understanding the aggregation and habitat use patterns of a species can aid the formulation and improved design of management strategies aiming to conserve vulnerable populations. We used photo-identification techniques and a novel remote underwater camera system to examine the population sizes, patterns of residency and habitat use of oceanic (Mobula birostris) and reef (Mobula alfredi) manta rays in Seychelles (5.42°S; 53.30°E) between July 2006 and December 2018. Sightings of M. birostris were infrequent (n = 5), suggesting that if aggregation areas for this species exist, they occur outside of the boundary of our study. A total of 236 individual M. alfredi were identified across all surveys, 66.5% of which were sighted at D’Arros Island (Amirante Group) and 22.5% at St. François Atoll (Alphonse Group). Males and females were evenly represented within the identified population. M. alfredi visited a cleaning station at D’Arros Island less frequently during dawn and dusk than at midday, likely due to the adoption of a crepuscular foraging strategy. The remote and isolated nature of the Amirante and Alphonse Group aggregation areas, coupled with the lack of a targeted mobulid fishery in Seychelles, suggests that with appropriate regulations and monitoring, the marine protected areas gazetted within these two groups will benefit the conservation of M. alfredi in Seychelles.

The south-western Indian Ocean (SWIO) is a region of global importance for marine mammal biodiversity, but our understanding of most of the species and populations found there is still rudimentary. The Indian Ocean Network for Cetacean Research (IndoCet) was formed in 2014 and is dedicated to the research of all cetacean species across the SWIO. Since 2019, there have been efforts to create a regional network for coordinated response to stranding events as well as training and capacity building in the SWIO region. The present analysis represents a first investigation of stranding data collected by various members and collaborators within the IndoCet network, covering over 14,800km of coastline belonging to nine countries/territories. Between 2000-2020, there were 397 stranding events, representing 1,232 individual animals, 17 genera and 27 species, belonging to six families: four balaenopterids, one balaenid, one physeterid, two kogiids, six ziphiids and 14 delphinids. Seven mass strandings were recorded: two were composed of three to 20 individuals and five composed of >20 individuals. Spatial analysis of stranding events indicated that local spatio-temporal clusters (excessive number of events in time and geographic space) were present in all countries/territories, except for the Comoros. The only significant cluster was detected on the southwest coast of Mauritius, just west of the village of Souillac. The SWIO region predominantly comprises relatively poor countries/territories, but imminent Blue/Ocean economy developments are prevalent throughout the region. This study highlights the importance of establishing baselines upon which any future potential impact from anthropogenic developments in the region can be measured.

To support and scale up global restoration efforts, the United Nations (UN) has proclaimed 2021–2030 the “UN Decade on Ecosystem Restoration.” The Decade offers significant opportunities for and challenges to restoration, in particular for Africa, a continent that has a large need and potential for restoration. We thus argue that the Decade must be a success in and for Africa, and for this to happen, opportunities and challenges to achieving its goals must be promptly identified, and considered in the planning and implementation of restoration. Here, we outline six key areas that should be considered at a strategic level by African countries during the Decade. These are: (1) ensuring effective oversight and governance relevant to Africa; (2) translating the goals to meet the African context; (3) making the case for restoration amid multiple development demands; (4) growing an African restoration community of practice based on regional need; (5) collaborating to improve restoration outcomes; and (6) establishing an Africa‐relevant evidence base for restoration. We believe that these six key areas—even though they are not all novel—are currently not addressed at a level that matches the scale of the problem on the continent. Although the specific actions to be taken under each key area are dependent on the restoration context, integrating these key areas in the planning and implementation of restoration efforts will likely lead to improved restoration outcomes during the Decade.

Abstract Historically, Cousine Island was used for agriculture and harvesting various seabird eggs, but following restoration efforts initiated in the 1990s, it has become an important nesting area for Seychelles seabirds. White‐tailed tropicbird (Phaethon lepturus), white tern (Gygis alba), and lesser (Anous tenuirostris) and brown noddy (Anous stolidus) populations were monitored on Cousine Island between 1997 and 2017 to determine the long‐term population responses to various environmental variables during the winter breeding season. White tern, brown noddy, and white‐tailed tropicbird populations are increasing, indicating that island conditions for breeding have improved for these species in the last 20 years. Lesser noddy populations are in decline, but not significantly, with winter air temperature significantly adding to this trend. Lesser noddies are true colonial nesters and are therefore potentially more affected by climatic conditions that result in nest failures and nearshore prey shortages. The relationship between numbers of seasonally breeding species (lesser and brown noddies) and those of year‐round breeders (white‐tailed tropicbirds and white terns) was also examined. Brown noddy population trends significantly predicted white‐tailed tropicbird and white tern winter breeding population trends, suggesting that these species populations respond similarly to local conditions. Data from this study establish a baseline for future population trend investigations and assessments of island conservation and management success.

Migratory marine species cross political borders and enter the high seas, where the lack of an effective global management framework for biodiversity leaves them vulnerable to threats. Here, we combine 10,108 tracks from 5775 individual birds at 87 sites with data on breeding population sizes to estimate the relative year-round importance of national jurisdictions and high seas areas for 39 species of albatrosses and large petrels. Populations from every country made extensive use of the high seas, indicating the stake each country has in the management of biodiversity in international waters. We quantified the links among national populations of these threatened seabirds and the regional fisheries management organizations (RFMOs) which regulate fishing in the high seas. This work makes explicit the relative responsibilities that each country and RFMO has for the management of shared biodiversity, providing invaluable information for the conservation and management of migratory species in the marine realm.

Documenting post-bleaching trajectories of coral reef communities is crucial to understand their resilience to climate change. We investigated reef community changes following the 2015/16 bleaching event at Aldabra Atoll, where direct human impact is minimal. We combined benthic data collected pre- (2014) and post-bleaching (2016–2019) at 12 sites across three locations (lagoon, 2 m depth; seaward west and east, 5 and 15 m depth) with water temperature measurements. While seaward reefs experienced relative hard coral reductions of 51–62%, lagoonal coral loss was lower (− 34%), probably due to three-fold higher daily water temperature variability there. Between 2016 and 2019, hard coral cover did not change on deep reefs which remained dominated by turf algae and Halimeda, but absolute cover on shallow reefs increased annually by 1.3% (east), 2.3% (west) and 3.0% (lagoon), reaching, respectively, 54%, 68% and 93% of the pre-bleaching cover in 2019. Full recovery at the shallow seaward locations may take at least five more years, but remains uncertain for the deeper reefs. The expected increase in frequency and severity of coral bleaching events is likely to make even rapid recovery as observed in Aldabra’s lagoon too slow to prevent long-term reef degradation, even at remote sites.

Funding for this study was provided by the SeaWorld Research and Rescue Foundation, the Save our Seas Foundation, the Monash University Malaysia Tropical Medicine and Biology Platform, Monash University Malaysia School of Science, Quadrant Energy, Australian Institute of Marine Science, The Western Australian Department of Environment and Conservation, The Four Seasons Resorts Maldives. Funding for SP came from Aqua-Firma, the Shark Foundation, the Save Our Seas Foundation and two private trusts.