Horn Island Research Articles

Snapshots of Coastal Ecology Using Multiproxy Analysis Reveals Insights Into the Preservation of Swamp and Marsh Environments Since the Late Pleistocene

AbstractThe southeastern United States Coastal Plain ecosystem contains baldcypress (Taxodium distichum) swamps and grass‐dominated marshes. These ecosystems also occurred on the exposed continental shelf during lower sea levels but are rarely preserved due to the mechanically erosive nature of transgression and regression. Two presently marine sites on the northeastern Gulf of Mexico's continental shelf contain well‐preserved woody terrestrial sediments that were the subject of previous studies. This study continues the investigation using geochemical (δ13C, δ15N, δ34S) and palynological characteristics of these formerly terrestrial sediments to determine if swamps and/or marshes existed at the time of deposition. The first site is located ∼20 km southeast of Horn Island, Mississippi (MS) and the core has terrestrial sediments radiocarbon dated to 11,066–10,228 (2σ) calibrated years BP (early Holocene). The second site is the “Alabama Underwater Forest” located ∼13 km south of Gulf Shores, Alabama (AL) and the cores have terrestrial sediments optically stimulated luminescence dated to 63 ka (±10 ka, 2σ) to 72 ka (±16 ka, 2σ) (late Pleistocene). Geochemical results for the MS sediments indicate a swamp‐to‐freshwater marsh transitional series, whereas the AL sediments indicate a swamp‐to‐saltwater marsh transitional series, both supported by palynological results. Further exploration of the geochemical results using linear discriminant analysis, trained with published geochemical data, supports the swamp and marsh interpretations. We conclude that the near‐pristine preservation of these woody deposits is not solely due to physical mechanisms, such as rapid burial, but is also coupled with anoxia‐ and euxinia‐driven biogeochemical reactions promoting wood and woody debris preservation in swamp and marsh environments.

Natural history of the Fuegian snipe (Gallinago stricklandii (Gray 1845): a resident bird at Cape Horn?

The Fuegian snipe Gallinago stricklandii (Gray, 1845) is one of the most enigmatic members of the family Scolopacidae Rafinesque, 1815. It is the least known species of the Gallinago genus and inhabits throughout the range of the biome of South American temperate forests, between the Maule region (36°S) and Cape Horn (56°S). In this biogeographical range, its reproductive and migratory habits are still poorly known. In this study, we report observations conducted between the years 2002 and 2023 in the Cape Horn National Park, with an emphasis on the most recent fieldwork on Horn Island. On this island, between January and October 2023, we recorded the autoecology of a family group composed of two adults and one juvenile. One of these adults was captured, banded, and measured in February 2023 (55°57.896’S - 67°13.478’W). The family group of G. stricklandii on Horn Island resided there during the summer, fall, winter, and spring seasons. This behavior contrasts with the migratory habit of the Magellanic snipe G. magellanica (King 1828), a better-known sympatric species. In addition to the resident habits of this family group and other individuals of G. stricklandii, we report new information about the morphology, feeding, and reproductive habits in the southern end of its distribution. This information recorded at the southern extreme of the American continent will enable new studies about this species and open up comparative analyses with other species of the cosmopolitan Scolopacidae family, which includes the world’s northernmost breeding birds at the boreal extreme of the Americas

On the distribution and habitat use of the sub-Antarctic fly Hyadesimyia clausa Bigot (Diptera, Tachinidae) according to citizen science.

Hyadesimyia clausa Bigot is a morphologically striking tachinid that inhabits the Sub-Antarctic Ecoregion of the Magallanes Region in Chile and Tierra del Fuego province in Argentina. Much of the distributional information about this species is restricted to the Cape Horn islands, which have extreme environmental conditions, but the species' natural history, range limits, and habitat use have never been described or confirmed. Our goals were to describe the distributional limits of this sub-Antarctic fly with the help of citizen science and use this information type to describe this tachinid's habitat use and potential biological interactions with nonvascular and vascular flora. We found that citizen science significantly increased our understanding of the extent of occurrence, expanding the known distributional range by 195 km to the north and 153 km to the west. On the contrary, the values for the area of occupancy were not significant, but the occupancy overlap between different records was very low. We confirmed that H. clausa's habitat uses peatlands and although we have not provided evidence of pollination or movement of spores, we hypothesized, that the walking activity of H. clausa could help move sperm from mosses and pollen from the flowers of vascular plants, so they could act as potential pollinators. Citizen science can reduce and eliminate some scientific knowledge shortfalls and propose new ecological questions that could increase our knowledge of extreme ecosystems.

Examining the effect of salinity on dolphin mortality using Lagrangian particle tracking in a hydrodynamic model

Numerous dolphins are found dead on beaches and waterways of the Gulf of Mexico and Mississippi Sound every year. In 2019 an unusual mortality event (UME) occurred when 337 deceased bottlenose dolphins were stranded between Louisiana, Mississippi, Alabama, and Florida. According to NOAA, based on observations of skin lesions or distinct ulcerative dermatitis and other internal pathologic findings and the environmental conditions during that period of time, the identified cause of this UME was determined to be protracted exposure to low salinity waters. Dolphin carcasses are often found stranded on beaches days after they die. Consequently, their initial place of death is unknown. In this study, an existing 2D hydrodynamic model (EFDC+ 11.2) of the Mississippi Sound simulated by Armandei et al. (2021) was used to track dolphin carcass movement and to simulate salinity at the time and location of each predicted dolphin's death. Particles within the Lagrangian particle tracking module were used to represent the movement of 19 dolphin carcasses. A large number of particles (virtual dolphin carcasses) were seeded throughout the model domain and tracked for five days. These results were used to hindcast each dolphin's original location of death. The results indicate that the most likely place of death for 12 dolphins stranded on the beaches of Mississippi, along with the two found on Ship and Horn Islands, was west of their stranding location., For both of the dolphins stranded on Dauphin Island, the most likely place of death was in the Mobile Bay area north of where they were found. The remaining three dolphins found dead on barrier islands, most likely originally died in close proximity to their stranding locations. The average simulated salinity of all the dolphins' most probable original place of death was below five except for two cases. These results are compared to the salinity of the Mississippi Sound during Bonnet Carré spillway opening and non-opening dates. The results highlight the significant impact of the spillway's opening on the reduction of salinity and its association with dolphin mortality.

Environmental factors and occurrence of horseshoe crabs in the northcentral Gulf of Mexico.

This study provides regional-scale data on drivers of horseshoe crab (Limulus polyphemus) presence along the northcentral Gulf of Mexico coast and has implications for understanding habitat suitability for sparse horseshoe crab populations of conservation concern worldwide. To collect baseline data on the relationship between environmental factors and presence of horseshoe crabs, we surveyed four sites from the Fort Morgan peninsula of Mobile Bay, Alabama (AL) to Horn Island, Mississippi (MS). We documented number, size and sex of live animals, molts, and carcasses as metrics of horseshoe crab presence and demographics for two years. Data were compared to in situ and remotely sensed environmental attributes to assess environmental drivers of occurrence during the time of study. Overall, greater evidence of horseshoe crab presence was found at western sites (Petit Bois and Horn Islands) compared to eastern sites (Dauphin Island, Fort Morgan peninsula), mediated by a combination of distance from areas of high freshwater discharge and interannual variation in weather. Higher sex ratios also were found associated with higher occurrence, west of Mobile Bay. Land cover, particularly Bare Land and Estuarine Emergent Wetland classes that are common to western sites, was most predictive of live animal and to some extent carcass occurrence. Our findings suggest that small-scale variation in habitat quality can affect occurrence of horseshoe crabs in sparse populations where density is not a limiting factor. Data from molts and carcasses were informative to supplement live animal data and may be useful to enhance ecological assessment and support conservation and management in regions with sparse populations.

Influence of antecedent geology on the Holocene formation and evolution of Horn Island, Mississippi, USA

Horn Island, one of the two most stable barriers along the Mississippi-Alabama chain (Cat, East and West Ship, Horn, West Petit Bois, Petit Bois, and Dauphin), provides critical habitat, helps regulate estuarine conditions in the Mississippi Sound, and reduces wave energy and storm surge before they reach the mainland shore. However, important details of the formation and evolution of the island in response to sea-level rise, storms, and antecedent geology remain unclear. This study integrates 2200 km of high-resolution geophysical data, 35 sediment cores, and 18 radiocarbon ages to better understand the geologic history of the island. Incised valleys of the Biloxi and Pascagoula Rivers underlie Horn Island and played a profound role in the evolution of the system. Within the incised valleys, sandy paleochannel deposits represent potential sediment sources during island development. Scour associated with wave and tidal ravinement processes liberated sand from the paleochannels and along with numerous other sizable sand sources on the shelf contributed to the formation and continued maintenance of Horn Island. Based on radiocarbon ages, transgressive ephemeral islands/shoals with no preserved shoreface existed at least 8000 cal yr BP and were frequently overwashed when sea-level rise rates were ~ 4–5 mm/yr. Approximately 5000 cal yr BP, coinciding with a deceleration in sea-level rise to about 1.4 mm/yr and attendant increased sand supply, radiocarbon ages associated with Horn Island's barrier complex and lower shoreface indicate a period of island stabilization. Seismic and sediment core data show a long history of westward lateral migration by longshore currents through tidal ravinement and inlet fill. Subsurface sand packages associated with tidal inlet fill and paleochannels are available for ravinement and may be important sand sources for Horn Island to maintain subaerial exposure with the expected accelerated future sea-level rise.

Response and recovery of Horn and Petit Bois Islands, Mississippi, USA to tropical cyclone impacts: 2004–2016

Horn and Petit Bois islands are two of five Mississippi (MS) barrier islands that provide physical protection from tropical cyclones threatening the MS Gulf Coast, in addition to critical habitat for the northern Gulf of Mexico (GOM). In September 2004, Hurricane Ivan removed a large volume of sediment from the eastern ends of Horn and Petit Bois islands with its 1 to 2 m storm surge and ~194 kph wind speeds. Then, in August 2005 Hurricane Katrina severely impacted the two islands again with its 3.5 to 5.5 m storm surge on Horn and Petit Bois islands, and estimated maximum sustained wind speeds of 204 kph at landfall in southeast Louisiana. Using topographic light detection and ranging (LIDAR) datasets from 2004 to 2016, spatial and temporal changes of the islands' area, sediment volumes, and shorelines were measured to ascertain their geomorphic responses and recovery rates following the impacts of these devastating tropical cyclones. During the 2004–05 hurricane seasons, Horn Island lost ~13.3% of its pre-hurricane Ivan land area, lost ~35.9% sediment volume, and had a total average shoreline change rate of −10 m/yr. Petit Bois Island also lost ~13.3% of its pre-Ivan land area, lost ~27% sediment volume, and had a shoreline change rate of −33 m/yr. Between 2005 (post-Katrina) and 2016, Horn Island recouped ~6.6% of its pre-Ivan land area and ~4.3% sediment volume, whereas Petit Bois Island recovered ~4% of its pre-Ivan land area and ~22.9% sediment volume. The overall averaged shoreline change rates between 2004 and 2016 were −2 m/yr for Horn Island and −3 m/yr for Petit Bois Island. These changes reflect that Horn Island is no longer stable, as its sediment supply cannot keep pace with the current rate of sediment loss, and that because Petit Bois Island's narrow central shoreline is retreating at a rate of 10 m/yr, the island is at risk of breaching during the next storm. Highlighting complex island response, the relationship between area and shoreline changes to that of volume changes was inconsistent.

Coastal Sand Frostweed, Crocanthemum arenicola Synonym: Helianthemum arenicola

Coastal sand frostweed is found on beach dunes, scrub, and sandhills. It is endemic to the Florida Panhandle, Mississippi, and Alabama coastal counties. After Hurricane Katrina, coastal sand frostweed became the plant with highest frequency on stable dunes on Horn Island, Mississippi (Lucas and Carter 2013).https://edis.ifas.ufl.edu/sg168
 Note: This fact sheet is also available as a chapter in a comprehensive manual titled Dune Restoration and Enhancement for the Florida Panhandle, Please see the manual for more information about other useful and attractive native plants for dunes and for further information about restoration and preservation techniques.

Tropicalization of the Northern Gulf of Mexico: Impacts of Salt Marsh Transition to Black Mangrove Dominance on Faunal Communities

The tropically associated black mangrove (Avicennia germinans) is expanding into salt marshes of the northern Gulf of Mexico (nGOM). This species has colonized temperate systems dominated by smooth cordgrass (Spartina alterniflora) in Texas, Louisiana, Florida and, most recently, Mississippi. To date, little is known about the habitat value of black mangroves for juvenile fish and invertebrates. Here we compare benthic epifauna, infauna, and nekton use of Spartina-dominated, Avicennia-dominated, and mixed Spartina and black mangrove habitats in two areas with varying densities and ages of black mangroves. Faunal samples and sediment cores were collected monthly from April to October in 2012 and 2013 from Horn Island, MS, and twice yearly in the Chandeleur Islands, LA. Multivariate analysis suggested benthic epifauna communities differed significantly between study location and among habitat types, with a significant interaction between the two fixed factors. Differences in mangrove and marsh community composition were greater at the Chandeleurs than at Horn Island, perhaps because of the distinct mangrove/marsh ecotone and the high density and age of mangroves there. Infaunal abundances were significantly higher at Horn Island, with tanaids acting as the main driver of differences between study locations. We predict that if black mangroves continue to increase in abundance in the northern GOM, estuarine faunal community composition could shift substantially because black mangroves typically colonize shorelines at higher elevations than smooth cordgrass, resulting in habitats of differing complexity and flooding duration.

Sensitivity analysis of the physical dynamics of the Fly River plume in Torres Strait

The intrusion in the Torres Strait of the Fly River plume polluted by mine tailings is an international water issue. To investigate the physical mechanisms involved in the intrusion process, numerical simulations were conducted to assess the relative influence of the bathymetry and the external forcing, namely the tides, the mean sea level slope across the strait, river runoff and wind forcing. The wind data from Horn Island, the only long-term wind station in the Torres Strait, is shown to be unreliable due to orographic effects. Mean sea level data from altimetry compare well with those from tide gauges in these shallow, reef-studded waters. The wind has a dominant effect on the mean sea level at seasonal and inter-annual periods. The resulting mean sea level difference across the strait fluctuated seasonally and strongly influenced the intrusion of the Fly River plume in the Torres Strait. The 3D finite-volume MOHID model reproduced the observation that the river plume starts by being stratified in the Gulf of Papua where it originates, and it mixes vertically when it enters the Torres Strait. The MOHID and the SLIM models were applied with different resolution to the Torres Strait and responded similarly to the external forcings. The predicted and observed Fly River plume intrusion in the eastern Torres Strait agreed well with each other, including the formation of patches due to flow reversals. However, the two models predicted a widely different Fly River plume in its far field in the western Torres Strait, the differences were attributed to the different bathymetry in the Australian and British-US bathymetry data for these poorly charted waters, which demonstrated the importance of the details of the bathymetry in controlling the extent of plume intrusion.

Effect of Habitat Complexity on Predator—Prey Relationships: Implications for Black Mangrove Range Expansion into Northern Gulf of Mexico Salt Marshes

ABSTRACT The tropically associated black mangrove (Avicennia germinans) is experiencing a climate-induced range shift and expanding into salt marshes of northern Florida, southern Louisiana and most recently, Horn Island, MS. To date, little is known about how black mangroves function as nursery habitat for important fishery species such as shrimps or how their increase may affect survival of such species. The main objective of our study was to determine habitat preference and survival rates of common, economically important penaeid shrimps in the presence and absence of the increasingly abundant tropical predator, the gray snapper (Lutjanus griseus). We also examined the effects of habitat identity and structure on juvenile white shrimp (Litopenaeus setiferus) and brown shrimp (Farfantepenaeus aztecus) behavior, using preference experiments in indoor mesocosms both with and without the predatory gray snapper. Results showed that shrimp prefer Spartina over Avicennia with or without predation risk. Surviv...

Holding back the tiger: Successful control program protects Australia from Aedes albopictus expansion.

BackgroundThe Asian tiger mosquito, Aedes albopictus, is an important vector of dengue, chikungunya and Zika viruses and is a highly invasive and aggressive biter. Established populations of this species were first recognised in Australia in 2005 when they were discovered on islands in the Torres Strait, between mainland Australia and Papua New Guinea. A control program was implemented with the original goal of eliminating Ae. albopictus from the Torres Strait. We describe the evolution of management strategies that provide a template for Ae. albopictus control that can be adopted elsewhere.Methodology / Principal findingsThe control strategy implemented between 2005 and 2008 targeted larval habitats using source reduction, insect-growth regulator and pyrethroid insecticide to control larvae and adults in the containers. However, the infrequency of insecticide reapplication, the continual accumulation and replacement of containers, and imminent re-introduction of mosquitoes through people’s movement from elsewhere compromised the program. Consequently, in 2009 the objective of the program changed from elimination to quarantine, with the goal of preventing Ae albopictus from infesting Thursday and Horn islands, which are the transport hubs connecting the Torres Strait to mainland Australia. However, larval control strategies did not prevent the species establishing on these islands in 2010. Thereafter, an additional strategy adopted by the quarantine program in early 2011 was harborage spraying, whereby the vegetated, well shaded resting sites of adult Ae. albopictus were treated with a residual pyrethroid insecticide. Inclusion of this additional measure led to a 97% decline in Ae. albopictus numbers within two years. In addition, the frequency of container treatment was increased to five weeks between treatments, compared to an average of 8 weeks that occurred in the earlier iterations of the program. By 2015 and 2016, Ae. albopictus populations on the two islands were undetectable in 70–90% of surveys conducted. Importantly, a comprehensive surveillance network in selected strategic areas has not identified established populations of this species on the Australian mainland.Conclusions / SignificanceThe program has successfully reduced Ae. albopictus populations on Thursday Island and Horn Island to levels where it is undetectable in up to 90% of surveys, and has largely removed the risk of mainland establishment via that route. The vector management strategies adopted in the later years of the program have been demonstrably successful and provide a practical management framework for dengue, chikungunya or Zika virus outbreaks vectored by Ae. albopictus. As of June 2016, Ae. albopictus had not established on the Australian mainland and this program has likely contributed significantly to this outcome.

Differential Predictors of Adult versus Juvenile Distributions of Two Coastal Pelagic, Surf Zone Fishes along the Northern Gulf of Mexico

AbstractAs coastal human populations increase and offshore fishery regulations become more stringent in the northern Gulf of Mexico, nearshore fisheries may be subjected to increased exploitation. Spanish Mackerel Scomberomorus maculatus and Florida Pompano Trachinotus carolinus are two nearshore, coastal migratory pelagic species vulnerable to undergoing changes in fishing pressure; however, information is incomplete in regards to understanding their current distributions and movement patterns, both of which are important for effective fishery management. We used a 2‐year (2011–2012) gill‐net and seine survey to assess surf zone distributions of Spanish Mackerel and Florida Pompano in the northern Gulf of Mexico (Horn Island, Mississippi, to Pensacola, Florida). Unbiased catch‐per‐unit‐effort estimates (by the delta method) were greatest in Alabama and during spring months. Lowest catches occurred during the warm summer months. Overall, subadult–adult Spanish Mackerel presence could be predicted (using a delta‐lognormal general linear model) by geographic area, beach habitat, and depth. Florida Pompano presence could be predicted by month and beach habitat. For both species, the abundance could not be predicted by any of the examined variables. Juvenile Florida Pompano presence, contrastingly, could be predicted by month and salinity, and abundance by month and water temperature. Both species had spatiotemporal variability in distribution and catch rates, but beach habitat appeared to be a better predictor for subadults and adults of both species, whereas month and salinity were better predictors for juvenile Florida Pompano catches. Greater catches generally corresponded with proposed migration patterns but also suggest that individuals, at least temporarily, leave the surf zone during the day in the warm summer months. Furthermore, although legal‐sized individuals of both species can co‐occur in the surf zone in the northern Gulf of Mexico, the increase in Spanish Mackerel presence with depth suggests that Spanish Mackerel fisheries could potentially move further offshore to avoid user conflict with Florida Pompano fisheries.Received March 16, 2016; accepted August 1, 2016 Published online October 14, 2016

Land Cover Data for the Mississippi–Alabama Barrier Islands, 2010–2011

Land cover on the Mississippi–Alabama barrier islands was surveyed in 2010–2011 as part of continuing research on island geomorphic and vegetation dynamics following the 2005 impact of Hurricane Katrina. Results of the survey include sub-meter GPS location, a listing of dominant vegetation species and field photographs recorded at 375 sampling locations distributed among Cat, West Ship, East Ship, Horn, Sand, Petit Bois and Dauphin Islands. The survey was conducted in a period of intensive remote sensing data acquisition over the northern Gulf of Mexico by federal, state and commercial organizations in response to the 2010 Macondo Well (Deepwater Horizon) oil spill. The data are useful in providing ground reference information for thematic classification of remotely-sensed imagery, and a record of land cover which may be used in future research.

Rediscovery of the 220-year-old holotype of the Banded Iguana, Brachylophus fasciatus (Brongniart, 1800) in the Paris Natural History Museum.

The Paris Natural History Museum herpetological collection (MNHN-RA) has seven historical specimens of Brachylophus spp. collected late in the 18^th and early in the 19th centuries. Brachylophus fasciatus was described in 1800 by Brongniart but its type was subsequently considered as lost and never present in MNHN-RA collections. We found that 220 year old holotype among existing collections, registered without any data, and we show that it was donated to MNHN-RA from Brongniart's private collection after his death in 1847. It was registered in the catalogue of 1851 but without any data or reference to its type status. According to the coloration (uncommon midbody saddle-like dorsal banding pattern) and morphometric data given in its original description and in the subsequent examination of the type in 1802 by Daudin and in 1805 by Brongniart we found that lost holotype in the collections. Another MNHN-RA specimen has Horn Islands (Wallis and Futuna) as the collection location but we show that most of the collections given to MNHN-RA by its collector, Louis Arnoux, have mixed localities in the MNHN-RA catalogues. We thus conclude that the locality is wrong and that the species never inhabited those islands located west of Western Samoa and north-east of Fiji.

Carers' perspectives on an effective Indigenous health model for childhood asthma in the Torres Strait.

To describe parents'/carers' views of the characteristics of a clinical service model shown to improve asthma outcomes. A randomised controlled study on education intervention for childhood asthma by Indigenous health care workers. Thursday Island, Horn Island and Bamaga. Thirty-five children received the intervention and 53 were in the control group. At the last study visit 12 months after enrolment, carers were asked to give feedback about the clinical service delivered by paediatric respiratory physicians and the asthma education intervention. Additional asthma education. Carers' responses to the open-ended questions were analysed separately by three Indigenous investigators who assigned codes and developed the themes. These were then cross-checked and combined to develop an overall interpretation of the data. The carers (n = 81) of 88 children in the Torres Strait region of North Queensland reported positively to the clinical service delivery. Service was rated as excellent = 26.8%, very good = 51.2%, good = 19.5% and poor = 2.4%. Parents'/carers' views about the clinical service model were grouped into seven themes: clear communication by health professionals, service delivery, professional approach, clear transfer of knowledge and education/clinical knowledge of asthma, established rapport/caregiver satisfaction, importance of coming into the local community, and areas of concern for the carers/parents. Community-based perspectives of an effective health service model include empowered Indigenous health care workers currently attached to the medical specialist service with elements of high expertise and appropriate cultural awareness that enabled clear communication and transfer of knowledge.

Habitat change on Horn Island, Mississippi, 1940-2010, determined from textural features in panchromatic vertical aerial imagery

Habitat-type land cover on Horn Island, Mississippi, northern Gulf of Mexico, was estimated for the years 1940 and 2010 using a combination of panchromatic imagery and 2010 ground survey data. A grey-level co-occurrence matrix was applied to compute reflectance coefficient of variation (CV) and texture indices. The relationships of 2010 CV ranges with known habitat types defined training regions of interest in the 1940 imagery as a substitute for 1940 ground data. Texture indices contrast, correlation, energy and entropy then served as input bands for maximum likelihood classifications which produced 1940 and 2010 habitat maps. Analysis determined that wetter habitats on Horn expanded linearly over the seven-decade period. This is attributed to constraints on sediment supply and the impacts of severe storms which led to decreases in soil depth to the water table. If this trend continues, marsh habitat will cover 31% of Horn Island’s land area by 2050.

Seagrasses in the Mississippi and Chandeleur Sounds and Problems Associated with Decadal-Scale Change Detection

Seagrass mapping data from a multitude of previous projects in the Mississippi and Chandeleur sounds were gathered and combined to provide information on seagrass change from 1940 to 2011. Seagrasses generally occur in three groups: (1) along the Mississippi mainland coastline dominated by Ruppia maritima, (2) on the north side of Mississippi Sound barrier islands dominated by Halodule wrightii, and (3) on the west side of the Chandeleur Islands dominated by Thalassia testudinum co-occurring with other seagrass species. The study area generally lost seagrasses over the 71-yr period, ostensibly due to loss or reduction of protective island barriers and reductions in water quality. An example of how the time series of maps generated in this project can be utilized to further investigate seagrass change was demonstrated with data from Horn Island, including problems associated with calculating change in seagrass area using data from previous investigations. Comparisons of seagrass area among various studies that used different mapping methods (seagrass extent vs. seagrass coverage vs. vegetated seagrass area) can result in overestimation of area change and misleading conclusions.

The use of climatologies and Bayesian models to link observations to outcomes; an example from the Torres Strait

After widespread coral bleaching in the Torres Strait in 2009-2010 a monitoring program was established under the National Environmental Research Program and run by the Torres Strait Regional Authority to identify ocean conditions that may lead to future bleaching. One component of this program was a real time ocean monitoring station located between Thursday and Horn Islands in the south-western part of the Torres Strait. A key outcome of the project was to make the scientific data and knowledge available to the local communities in a form that they could engage with and with which they could act to instigate outcomes relevant to their needs. The project developed climatologies to give context to the temperature data allowing for historical limits to define the significance of the real time data as related to the longer term mean. This allowed the identification of 'normal', 'significant' and 'extreme' temperature events which could be linked into appropriate responses. Bayesian models were used to encapsulate the current scientific knowledge about the drivers and responses involved in coral bleaching. These models were used to convert the environmental parameters to an output index reflecting the current and future likelihood of coral bleaching occurring. Two web sites were used to integrate the real time data, climatology data and the bleaching indices generated from the Bayesian models. The first was a more technical site developed for the local environmental managers within the Torres Strait Regional Authority, the second was targeted at the general public with a display located within the local radio station and broadcast on a daily basis. Engagement with the project has been high to the point where additional monitoring stations and data display kiosks are to be installed in the near future. The combination of climatologies to give context and conceptual models to embody system knowledge has allowed the project to go from delivering simple measurements to being able to deliver knowledge about the system in a format that engages the local community and that can be used to facilitate environmental management outcomes.

Cardicola langeli sp. n. (Digenea: Aporocotylidae) from heart of sheepshead, Archosargus probatocephalus (Actinopterygii: Sparidae) in the Gulf of Mexico, with an updated list of hosts, infection sites and localities for Cardicola spp.

Cardicola langeli n. sp. (Digenea: Aporocotylidae) infects the heart of sheepshead, Archosargus probatocephalus (Walbaum, 1792) (Perciformes: Sparidae) in the northern Gulf of Mexico off Horn Island (type locality), Mississippi, USA. The new species is described herein using light and scanning electron microscopy of adult specimens and can be most easily distinguished from the other 24 accepted species of Cardicola Short, 1953 by the combination of having (i) an ovovitelline duct that extends anteriad and that (ii) is posterior to the ootype, (iii) a male genital pore that is lateral to the oviducal seminal receptacle and (iv) a female genital pore lateral to the ootype. The new species is the only member of Cardicola so-far reported to have tegumental spines that are distally flattened and broad, rather than pointed. The new species generally resembles the two other species of Cardicola that infect sparids, i.e. Cardicola cardiocolum (Manter, 1947) (type species) from jolthead porgy, Calamus bajonado (Block et Schneider), in the Gulf of Mexico and Cardicola aurata Holzer, Montero, Repullés, Sitja-Bobadilla, Alvarez-Pellitero, Zarza et Raga, 2008, from gilthead seabream, Sparus aurata Linnaeus, in the Mediterranean Sea, by having a spheroid anterior sucker with concentric rows of minute spines anterior to the mouth and by having a similar general arrangement of the vitellarium, gonads and genitalia. However, it differs from them by having the combination of the aforementioned five features plus asymmetrical posterior caeca and a dextral posterior caecum that extends beyond the posterior margin of the ovary. Probable eggs of C. langeli n. sp. that contain a ciliated miracidium infect gill epithelium and are spheroid. An updated list of hosts, infection sites and geographic localities for the 25 accepted species of Cardicola is provided.