Swan Islands Research Articles

Beneficial use of sediments to restore a Chesapeake Bay marsh island

Despite rapidly expanding interest in the use of natural coastal habitats for their ability to protect against erosion and flooding, implementation of coastal natural infrastructure (NI) projects has been limited to date. Uncertainty over how the benefits of NI will change over time as they mature and adapt to changing environmental drivers, and a lack of well-documented demonstrations of NI, are often cited as roadblocks to their widespread acceptance. Here, we begin to fill that knowledge gap by describing implementation and early (3 years post-implementation) monitoring results of an NI project at Swan Island, MD. Swan is an uninhabited marsh island in mid-Chesapeake Bay, United States whose position renders it a natural wave break for the downwind town of Ewell, MD. Prior to project implementation, Swan had experienced significant losses in areal extent due to subsidence and erosion. To reverse this trend, the island was amended with dredged sediments in the winter of 2018–2019. The overarching goal was to preserve the Island’s ability to serve as a wave break and make it more resilient to future sea level rise by increasing the elevation of the vegetated platform, while also increasing the diversity of habitats present. A monitoring program was implemented immediately after sediment placement to document changes in the island footprint and topography over time and to evaluate the extent to which project goals are met. Data from the initial three years of this effort (2019 through 2022) indicate an island that is still actively evolving, and point to the need for rapid establishment of vegetative communities to ensure success of coastal NI.

Active ocean–continent transform margins: seismic investigation of the Cayman Trough-Swan Island ridge-transform intersection

SUMMARY The southern boundary of the Cayman Trough in the Caribbean is marked by the Swan Islands transform fault (SITF), which also represents the ocean–continent transition of the Honduras continental margin. This is one of the few places globally where a transform continental margin is currently active. The CAYSEIS experiment acquired an ∼165-km-long seismic refraction and gravity profile (P01) running across this transform margin, and along the ridge-axis of the Mid-Cayman Spreading Centre (MCSC) to the north. This profile reveals not only the crustal structure of an actively evolving transform continental margin, that juxtaposes Mesozoic-age continental crust to the south against zero-age ultraslow spread oceanic crust to the north, but also the nature of the crust and uppermost mantle beneath the ridge-transform intersection (RTI). The traveltimes of arrivals recorded by ocean-bottom seismographs (OBSs) deployed along-profile have been inverse and forward modelled, in combination with gravity modelling, to reveal an ∼25-km-thick continental crust that has been continuously thinned over a distance of ∼65 km to ∼10 km adjacent to the SITF, where it is juxtaposed against ∼3–4-km-thick oceanic crust. This thinning is primarily accommodated within the lower crust. Since Moho reflections are only sparsely observed, and, even then, only by a few OBSs located on the continental margin, the 7.5 km s–1 velocity contour is used as a proxy to locate the crust–mantle boundary along-profile. Along the MCSC, the crust–mantle boundary appears to be a transition zone, at least at the seismic wavelengths used for CAYSEIS data acquisition. Although the traveltime inversion only directly constrains the upper crust at the SITF, gravity modelling suggests that it is underlain by a higher density (>3000 kg m–3) region spanning the width (∼15 km) of its bathymetric expression, that may reflect a broad region of metasomatism, mantle hydration or melt-depleted lithospheric mantle. At the MCSC ridge-axis to the north, the oceanic crust appears to be forming in zones, where each zone is defined by the volume of its magma supply. The ridge tip adjacent to the SITF is currently in a magma rich phase of accretion. However, there is no evidence for melt leakage into the transform zone. The width and crustal structure of the SITF suggests its motion is currently predominantly orthogonal to spreading. Comparison to CAYSEIS Profile P04, located to the west and running across-margin and through 10 Ma MCSC oceanic crust, suggests that, at about this time, motion along the SITF had a left-lateral transtensional component, that accounts for its apparently broad seabed appearance westwards.

Long-term monitoring of two endangered freshwater mussels (Bivalvia: Unionidae) reveals how demographic vital rates are influenced by species life history traits.

To meet monitoring and recovery planning needs, demographic vital rates of two endangered freshwater mussels (Bivalvia: Unionidae)-the Cumberlandian Combshell (Epioblasma brevidens, Lea 1831) and Oyster Mussel (Epioblasma capsaeformis, Lea 1834), species endemic to the Tennessee and Cumberland river basins, U.S.A-were estimated and compared using census methodologies. Annual variation in population density and size, recruitment rate, mortality rate, sex ratios, and female fecundity of both species were observed from 2004-2014 at three fixed sites, spanning a 33.8 kilometer (KM) reach of the Clinch River, Hancock County, Tennessee. Mean population size of E. brevidens estimated from 11 censuses was 2,598 individuals at Swan Island (KM 277.1), 8,744 at Frost Ford (KM 291.8), and 879 at Wallen Bend (KM 309.6); collectively, these demes grew at an annual rate of 7% over the study period. Mean population size of E. capsaeformis was 7,846 individuals at Swan Island, 265,442 at Frost Ford, and 11,704 at Wallen Bend; collectively, these demes grew at an annual rate of 6%. Population size, variability in population growth, recruitment, and mortality of the shorter-lived E. capsaeformis (maximum age = 16 yrs, rarely >10 yrs) were higher than those of the longer-lived E. brevidens (maximum age = 25 yrs). Stream discharge was associated with realized per-capita population growth rate for both species when juvenile (Ages 1-3) data was included. Linear regression analysis showed that the growth rate of E. brevidens was negatively associated with median annual discharge (p = 0.0274) and that growth rate of E. capsaeformis was negatively associated with the number of days having extreme high discharge preceding a census (p = 0.0381). Fecundity of female E. brevidens averaged 34,947 (SE = 2,492) glochidia and ranged from 18,987 to 56,151, whereas fecundity of female E. capsaeformis averaged 9,558 (SE = 603) glochidia and ranged from 3,456 to 22,182. Estimated vital rates indicated that the two species are characterized by different life-history strategies, with E. brevidens exhibiting a periodic strategy (between K- and r-selected) and E. capsaeformis an opportunistic strategy (r-selected). These life history strategies are likely influenced by each species' longevity and habitat preference, in addition to the life histories and population dynamics of their primary fish hosts.

A framework for evaluating island restoration performance: A case study from the Chesapeake Bay.

The use of natural habitats for coastal protection (also known as Nature‐Based Solutions or NBS) in place of engineered structures like breakwaters and seawalls can yield a wide range of ecological and economic benefits. Despite these advantages, NBS are not commonly implemented for shoreline protection due to uncertainty over the amount of protection afforded by each unique feature and how protective capacity and ecological benefits are likely to change over time as NBS mature and adapt to changing environmental drivers. Here, we highlight the recent restoration of Swan Island in the Chesapeake Bay, Maryland, USA, and the collaborative approach used to evaluate post‐construction performance, as a framework for quantitative evaluation of NBS projects. At Swan Island, 60 000 cubic yards of dredged sediment were used to elevate and restore the island's footprint with an emphasis on increasing its protective and ecological benefits and long‐term resilience to sea‐level rise. Five entities have leveraged resources to quantify the benefits and efficacy of island restoration by conducting pre‐ and post‐restoration monitoring, which supports the development of an integrated, simulation model that includes three “measured” system parameters: wave height, vegetative biomass, and island profile (i.e., elevations). The model will be used to predict island performance under a range of different system scenarios and used to inform adaptive management options. Results will demonstrate the efficacy of leveraging natural and engineered processes to restore island systems while providing a framework for quantifying NBS. Integr Environ Assess Manag 2022;18:42–48. © 2021 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC). This article has been contributed to by US Government employees and their work is in the public domain in the USA.

ISLAND RESTORATION TO MEET 'TRIPLE-WIN' ENGINEERING WITH NATURE OUTCOMES

The coastal islands and marshes of Chesapeake Bay USA, are disappearing along with the ecosystem services and infrastructure/shoreline protection they provide. To counter such losses, the USACE Baltimore District is restoring historic island footprints using dredged sediments. Islands constitute an important natural and nature-based feature (NNBF) that meet the 'triple win outcomes' of USACE's Engineering With Nature (EWN) initiative, by providing economic, social and environmental benefits. Here we highlight the restoration and monitoring of Swan Island using 61,000 cubic yards of dredged sediment. The creation/expansion of Swan Island, is expected to produce significant benefits in terms of ecosystem services, increased resilience to future sea level rise, and abatement of erosive losses to an adjacent coastal community. The pre- and post-restoration monitoring and model development by project partners will serve to quantify the benefits and efficacy of the island restoration thereby facilitating island restoration as a viable NNBF option in the future.Recorded Presentation from the vICCE (YouTube Link): https://youtu.be/2kvSVcH2KuE

History of zoological research in the Crimean Nature Reserve: vertebrates

The present work is a historical and biographical sketch of the formation and development of research in one of the first nature reserves in Russia. The article describes the main milestones in the study of vertebrates in the past and the stages of scientific research in the Crimean Nature Reserve in the XX-XXI centuries. It is shown that by 1925 the vertebrate fauna of the mountain Crimea was poorly studied, and the formation and operation of the biological station in the Crimean Reserve marked the beginning of comprehensive research not only in the mountains, but also in the steppe. The reorganization of the Reserve into a hunting Reserve in 1957 did not affect the level and scale of scientific research. In 1964-1968, a comprehensive theme on beechwood forests was completed, and in 1970-1974, a theme on birds and mammals of the Crimea was conducted as well. In 1974-1976 the work of the zoological group went to the international level in connection with the inclusion of Swan Islands in the number of the Ramsar Sites of the USSR. Since 1983, scientific research has been conducted under the program "Nature Records" within the boundaries of the reserve. In 1991, the institution was returned to the status of a nature reserve. Zoological research is carried out by full-time employees with the participation of scientists from various research centers working on international projects. After the reunification of the Crimea with Russia in 2014, the Crimean Reserve is undergoing a period of reorganization. And in September 2018 its mountain and forest part gets the status of a National Park. The “Swan Islands” ornithological branch becomes an independent nature reserve.

Imaging the rupture process of the 10 January 2018 MW7.5 Swan island, Honduras earthquake*

The 10 January 2018 MW7.5 Swan island, Honduras earthquake occurred on the Swan island fault, which is a transform plate boundary between the North American and Caribbean plates. Here we back-project the rupture process of the earthquake using dense seismic stations in Alaska, and find that the earthquake ruptured at least three faults (three stages) for a duration of ~40 s. The rupture speed for the longest fault (stage 3) is as fast as 5 km/s, which is much faster than the local shear wave velocity of ~4 km/s. Supershear rupture was incidentally observed on long and straight strike-slip faults. This study shows a supershear rupture that occured on a strike-slip fault with moderate length, implying that supershear rupture might commonly occur on large strike-slip earthquakes. The common occurrence of supershear rupture on strike-slip earthquakes will challenge present understanding of crack physics, as well as strong ground motion evaluation in earthquake engineering.

Tsunami hazard in the Caribbean coast of Honduras due to large earthquakes occurred along the Cayman Trough at the northwest boundary of Caribbean plate

ABSTRACT In 2018, a large earthquake (Mw7.6) occurred in the Swan Island Fault zone at the northwest boundary of the Caribbean plate. This earthquake generated a small tsunami of 20 cm. However, Puerto Cortes in Honduras is located close to the Swan Island Fault zone. Evaluation of tsunami hazard at Puerto Cortes due to large earthquakes along the fault zone is important. We first estimated the fault parameters of the 2018 Swan Island earthquake using W-phase inversion technique. Then, the moment magnitude of 7.6, the fault length of 134 km, the fault width of 24 km, and the slip amount of 5.1 m were estimated. In addition to those estimates, a small fault dimension of the earthquake, 40 km × 20 km, with a slip amount of 20.8 m was considered. Those two fault models were used to compute tsunami inundation at Puerto Cortes. The tsunami computed from the small fault inundated a large area in Puerto Cortes including the port area. The effect of co-seismic horizontal displacement of ocean floor also enhanced the tsunami inundation at Puerto Cortes. Those results indicate that preparation for future tsunami hazard in Puerto Cortes is important although no significant tsunami was generated historically.

Evaluation of Earthquake Magnitude Estimation and Event Detection Thresholds for Real-Time GNSS Networks: Examples from Recent Events Captured by the Network of the Americas

Abstract Several studies have shown that real-time (RT) Global Navigation Satellite Systems (GNSS) measurements can provide an estimate of an earthquake’s moment magnitude (Mw) using scaling laws that relate peak ground displacements (PGDs) and hypocentral distance with Mw. In this study, we use data from GNSS stations operated by UNAVCO as part of the National Science Foundation Geodetic Facility for the Advancement of Geoscience (GAGE) that comprises the Network of the Americas (NOTA) to show that precise point positioning (PPP) solutions distributed in RT during five recent earthquakes could be used to calculate Mw rapidly and reliably. We analyze solutions distributed by UNAVCO during the 8 September 2017 Mw 8.2 Tehuantepec, Mexico, 10 January 2018 Mw 7.5 Great Swan Island, Honduras, 23 January 2018 Mw 7.9 Gulf of Alaska earthquake, and the 4 July 2019 Mw 6.4 and 6 July 2019 Mw 7.1 Ridgecrest, California, earthquakes. We find that RT-GNSS Mw estimates consistent with Advanced National Seismic System Comprehensive Earthquake Catalog values are available tens of seconds to a few minutes after the event origin time. The speed with which an estimate is available is dependent on the proximity to the epicenter of the closest NOTA stations. The results demonstrate that RT-GNSS networks could be used to mitigate the problem of magnitude saturation observed in seismic-based earthquake early warning (EEW) systems. RT-GNSS effectively expands the spectrum of events for which a seismic EEW system can provide accurate warnings of impending ground shaking and provides an independent verification of seismically derived magnitudes. We also analyze the RT-PPP solutions from more than 800 RT-GNSS stations to determine the ambient-noise levels of each NOTA station and combine that with PGD magnitude scaling laws to construct regional network sensitivity maps for the NOTA network. Such maps may be used to determine “blind spots” or regions of lower sensitivity in RT-GNSS networks under consideration for EEW.

A revision of macrophytobenthos of the “Lebyazh’i Ostrova” Nature Reserve (Black Sea)

A revision of the marine macrophytes flora of the Crimean Nature Reserve branch “Lebyazh’i ostrova” (“Swan Islands”) was carried out. The flora includes 97 species (hereinafter - including infraspecific taxa): Chlorophyta - 30, Ochrophyta - 11, Rhodophyta - 47, Tracheophyta - 7, Charophyta - 2; taxonomic structure: 8 classes, 22 orders, 31 families, 51 genera. The macrophyte flora has an oligosaprobic nature; short vegetation species dominate in terms of vegetation period duration, but perennial species have a fairly high proportion too. Among halobility groups, marine and brackish-water species prevail. Among phytogeographic groups (combined into two complexes) a warm-water complex dominates, with a high contribution of cosmopolitan species. In general, the ecological and floristic indicators of macrophytobenthos are close to those established for the Egorlytsko-Tendrovsko-Dzharylgachsko-Perekopsky hydro-botanical region of the Black Sea. The rare fraction of flora (taking into account regional, national and international nature conservation documents) includes 27 species. Within protected marine and lagoon water areas, biotopes under the special protection of the EU Habitats Directive are located (Council Directive 92/43/EEC); the nature reserve is a structural element of the Emerald Network and is designated as Wetlands of International Importance.

Seismic investigation of an active ocean–continent transform margin: the interaction between the Swan Islands Fault Zone and the ultraslow-spreading Mid-Cayman Spreading Centre

SUMMARY The Swan Islands Transform Fault (SITF) marks the southern boundary of the Cayman Trough and the ocean–continent transition of the North American–Caribbean Plate boundary offshore Honduras. The CAYSEIS experiment acquired a 180-km-long seismic refraction and gravity profile across this transform margin, ∼70 km to the west of the Mid-Cayman Spreading Centre (MCSC). This profile shows the crustal structure across a transform fault system that juxtaposes Mesozoic-age continental crust to the south against the ∼10-Myr-old ultraslow spread oceanic crust to the north. Ocean-bottom seismographs were deployed along-profile, and inverse and forward traveltime modelling, supported by gravity analysis, reveals ∼23-km-thick continental crust that has been thinned over a distance of ∼70 km to ∼10 km-thick at the SITF, juxtaposed against ∼4-km-thick oceanic crust. This thinning is primarily accommodated within the lower crust. Since Moho reflections are not widely observed, the 7.0 km s−1 velocity contour is used to define the Moho along-profile. The apparent lack of reflections to the north of the SITF suggests that the Moho is more likely a transition zone between crust and mantle. Where the profile traverses bathymetric highs in the off-axis oceanic crust, higher P-wave velocity is observed at shallow crustal depths. S-wave arrival modelling also reveals elevated velocities at shallow depths, except for crust adjacent to the SITF that would have occupied the inside corner high of the ridge-transform intersection when on axis. We use a Vp/Vs ratio of 1.9 to mark where lithologies of the lower crust and uppermost mantle may be exhumed, and also to locate the upper-to-lower crustal transition, identify relict oceanic core complexes and regions of magmatically formed crust. An elevated Vp/Vs ratio suggests not only that serpentinized peridotite may be exposed at the seafloor in places, but also that seawater has been able to flow deep into the crust and upper mantle over 20–30-km-wide regions which may explain the lack of a distinct Moho. The SITF has higher velocities at shallower depths than observed in the oceanic crust to the north and, at the seabed, it is a relatively wide feature. However, the velocity–depth model subseabed suggests a fault zone no wider than ∼5–10 km, that is mirrored by a narrow seabed depression ∼7500 m deep. Gravity modelling shows that the SITF is also underlain, at >2 km subseabed, by a ∼20-km-wide region of density >3000 kg m−3 that may reflect a broad region of metamorphism. The residual mantle Bouguer anomaly across the survey region, when compared with the bathymetry, suggests that the transform may also have a component of left-lateral trans-tensional displacement that accounts for its apparently broad seabed appearance, and that the focus of magma supply may currently be displaced to the north of the MCSC segment centre. Our results suggest that Swan Islands margin development caused thinning of the adjacent continental crust, and that the adjacent oceanic crust formed in a cool ridge setting, either as a result of reduced mantle upwelling and/or due to fracture enhanced fluid flow.

Состав пищи креветки Palaemon adspersus Rathke, 1837 (Crustacea Decapoda, Palaemonidae) в Каркинитском заливе Чёрного моря в сентябре 2016 г.

Palaemon adspersus — обитатель верхней части шельфа (0–30 м) умеренной и субтропической климатических зон Восточной Атлантики, достигающий в своём распространении на севере 60° с. ш. (воды Норвегии), а на юге — атлантических вод Марокко. Питание этого вида изучали в разное время в различных частях его ареала, но из черноморской части ареала оно описано впервые в этой работе. Исследовано содержимое 218 желудков взрослых креветок (74 из них имели пищу в желудке, и у 30 особей желудки были полными), собранных в сентябре 2016 г. из промысловых вентерей в районе Лебяжьих островов Каркинитского залива на глубине, не превышающей 1,5 м. Малое количество желудков с пищей объясняется длительным пребыванием креветок в вентерях до момента их фиксации. Креветки имели длину тела (от заднего края орбит до конца тельсона) 31,5–58,1 мм (самцы — 33,9–44,1 мм с модой 37 мм). Соотношение полов составляло примерно 1 : 8 (11,7 % самцов и 82,3 % самок). Самки были представлены двумя группами особей. Самки с гонадами во II стадии зрелости имели модальные размеры 37 мм. Самки с гонадами в III стадии зрелости имели модальные размеры 47 мм. Следовательно, в сентябре часть самок спарились, перелиняли, у них в гонадах начался вителлогенез. P. adspersus — бентофаг-эврифаг. Его пищевой спектр охватывает широкий круг объектов питания — от детрита и растительных остатков до брюхоногих моллюсков, высших раков, в том числе креветок, и рыбы. P. adspersus в первую очередь собиратель — детритофаг и некрофаг, 70 % объёма виртуального пищевого комка которого занимают детрит и трупы высших ракообразных. Между тем по отношению к полихетам он ведёт себя как нападающий хищник, а к брюхоногим моллюскам — как пасущийся. Сравнение состава пищи P. adspersus в Каркинитском заливе (2016) с таковым креветки в Балтийском море (1977), в атлантических (1987) и средиземноморских (1993–1994) водах побережья Испании обнаруживает его пространственно-временную квазистабильность. На основе совокупности имеющихся данных о составе пищи P. adspersus его следует отнести к хищникам-оппортунистам сублиторали.

PASSER HISPANIOLENSIS IS A NEW NESTING SPECIES ON NORTH-WESTERN COAST OF THE CRIMEAN PENINSULA

Aim. The aim of the research is to study the potential nesting sites of the Spanish sparrow (Passer hispaniolensis) on the northwest coast of Crimea. Methods. Material was compiled during 2016-2018. The generally accepted methods of road and foot route census study were applied. Nesting stations were explored: nests of storks, birds of prey and corvids, forest belts and reed beds. Results. On the basis of research, the presence of Passer hispaniolensis in the north-western Crimea, in particular, within the borders of the Lebyazhy Islands («Swan Islands») specially protected natural area, has been established. It is revealed that for nesting, this species of sparrow prefers the areas close to fields and is not often found in human settlements. During the nesting period, an increase in the number from 15 to 45 pairs was noted. The greatest number of breeding pairs of spanish sparrow is found in the nests of the white stork. Late arriving birds form colonies on trees in close proximity to stork nests. Conclusion. Nesting of Passer hispaniolensis is most likely due to changes in the hydrological regime and land use structure, since rice crop rotation (until 2014) has been replaced by other grain crops (barley, wheat) and tilled crops (sunflower, maize). Thus, at present, the breeding ornithofauna of the protected area is represented by 92 species of birds.

GPS constraints on deformation in northern Central America from 1999 to 2017, Part 1 – Time-dependent modelling of large regional earthquakes and their post-seismic effects

We use continuous and campaign measurements from 215 GPS sites in northern Central America and southern Mexico to estimate coseismic and afterslip solutions for the 2009 M w = 7.3 Swan Islands fault strike-slip earthquake and the 2012 M w = 7.3 El Salvador and M w = 7.4 Guatemala thrust-faulting earthquakes on the Middle America trench. Our simultaneous , time-dependent inversion of more than 350 000 daily GPS site positions gives the first jointly consistent estimates of the coseismic slips for all three earthquakes, their combined time-dependent post-seismic effects and secular station velocities corrected for both the co-seismic and post-seismic deformation. Our geodetic slip solutions for all three earthquakes agree with previous estimates that were derived via static coseismic-offset modelling. Our time-dependent model, which attributes all transient post-seismic deformation to earthquake afterslip, fits nearly all of the continuous GPS site position time-series within their several-millimetre position noise. Afterslip moments for the three earthquakes range from 35 to 140 per cent of the geodetic coseismic moments, with the largest afterslip estimated for the 2012 El Salvador earthquake along the weakly coupled El Salvador trench segment. Forward modelling of viscoelastic deformation triggered by all three earthquakes for a range of assumed mantle and lower crustal viscosities suggests that it accounts for under 20 per cent of the observed post-seismic deformation and possibly under 10 per cent. Our results thus point to afterslip as the primary and perhaps dominant mode of post-seismic deformation for these C The Author(s)

Preliminary results for the rupture process of Jan. 10, 2018, <i>M</i>w7.6 earthquake at east of Great Swan Island, Honduras

Preliminary results for the rupture process of Jan. 10, 2018, <i>M</i>w7.6 earthquake at east of Great Swan Island, Honduras

Rejection, Reception, and Rejection Again: Women in Oregon's World War II Shipyards

In this Reflection Essay, Diane Simmons describes the research she conducted for her book, The Courtship of Eva Eldridge, a biographical narrative of a young woman during World War II. Eldridge worked at a cafeteria in the Kaiser Swan Island shipyard beginning in 1944. During her research, Simmons looked at runs of Kaiser's company newsletter, The Bo's'n's Whistle, to give her insight into Eldrige's experience. Through that research, Simmons found that women first faced a cold reception, but by 1944 when Eldridge arrived, the company's efforts to make the environment more appealing to women was evident. After being integrated into the workforce, many women then propaganda urging them back into the domestic sphere.

Updated Population and Habitat Comments About the Reptiles of the Swan Islands, Honduras

We discuss the results of a recent trip to the isolated Swan Islands, Honduras. We include habitat notes for each of the reptilian species we encountered. Also, we compare nine of the 13 reptilian species previously reported from these islands with the only previous reptilian species list that contains natural history notes. Comparisons between our 2012 experiences and those of a 1912 trip demonstrate that the following changes have occurred in the past century: three lizard species have been introduced by humans; two of the four island endemic reptilian species remain common, as they were in 1912; one endemic lizard species appears to have declined drastically in numbers; and the single endemic snake species remains as poorly known now as it was in 1912.

Studies on Neotropical Phasmatodea XVI: Revision of Haplopodini Günther, 1953 (rev. stat.), with notes on the subfamily Cladomorphinae Bradley & Galil, 1977 and the descriptions of a new tribe, four new genera and nine new species(Phasmatodea: "Anareolatae": Phasmatidae: Cladomorphinae).

Studies on Neotropical Phasmatodea XVI: Revision of Haplopodini Günther, 1953 (rev. stat.), with notes on the subfamily Cladomorphinae Bradley & Galil, 1977 and the descriptions of a new tribe, four new genera and nine new species(Phasmatodea: "Anareolatae": Phasmatidae: Cladomorphinae).

Variation in recruitment and the establishment of alternative community states.

Mussel beds and rockweed stands (fucoid algae) have been shown to be ilternative states on rocky intertidal shores in New England, and here the hypothesis that variation in recruitment provides opportunity for the development of alternative community states was tested. Disturbance by ice scour opens patches for development of alternative states, and in winter 1996-1997, 60 experimental clearings of differing sizes were established on Swan's Island, Maine, USA. Half of the plots were re-cleared during the winter of 2010-2011. Recruitment data for barnacles, mussels, and fucoid algae collected from 1997 to 2012 were used to (1) test for persistence of scale-dependent thresholds, (2) estimate the magnitudes and sources of variation, (3) fit a surface of alternative states as defined by the cusp catastrophe, and (4) test if 1997 recruitment would predict 2010-2011 recruitment in re-scraped plots (i.e., a test of divergence, which is expected in systems with alternative states). For barnacles and mussels, recruitment varied enormously year to year and among sites, but showed consistent patterns over the long-term with respect to clearing size. Average recruitment prior to re-clearing was a good predictor of recruitment afterwards. In contrast, over 50% of the variance in fucoid recruitment was unexplained with weak effects among years and locations. Past fucoid recruitment was a poor predictor of subsequent recruitment. The cusp analysis indicated that fucoid recruitment defines the alternative states. Fucoid recruitment was largely unpredictable and suggests long-term, small-scale priority effects drive the development of alternative states. These observations strongly reinforce the notion that long-term and well- replicated experiments are necessary to develop robust tests of ecological theory.

An investigation into the Swan Island Honduras collecting event ofTiaporus fuliginosusCope (Reptilia: Teiidae) and its systematic status

Abstract Confusion exists in the literature concerning the collecting event of the teiid lizard Tiaporus fuliginosus. We investigated the literature and documents stored at the Smithsonian Institution Archives involving the collector of those specimens in an effort to resolve that confusion. We conclude that the type series was collected on the Swan Islands of Honduras by Charles H. Townsend during 1887. We also provide a redescription of that nominal form and show that it is a valid species that should be called Ameiva fuliginosa. We also examined the type series of A. panchlora from Old Providence, Colombia and confirm that its 1950 placement as a junior synonym of A. fuliginosa is correct.