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Barrier islands in Louisiana and elsewhere in the northern Gulf of Mexico region provide valuable breeding habitat for numerous waterbird species; however, these islands are also deteriorating at an alarming rate. Management and conservation of waterbird species in these dynamic environments require a better understanding of the breeding biology for northern Gulf of Mexico populations. Productivity parameters were investigated for Royal (Thalasseus maximus) and Sandwich (T. sandvicensis) terns at the Isles Dernieres Barrier Island Refuge in Terrebonne Parish, Louisiana, during the 2009 and 2010 breeding seasons. Mean hatching success for Royal Tern was 77% (n = 169 nests), while Sandwich Tern hatching success was 75% (n = 130 nests). For both Royal and Sandwich terns, the estimated probability that a chick survived from hatching to fledging age was 55% (n = 630 nestlings). Overall, estimated breeding success for Royal and Sandwich terns was 42.3% and 41%, respectively. Chick growth rates were similar for both species and among islands, suggesting similar habitat quality among islands of Isles Dernieres Barrier Island Refuge. Growth rates (K) for both Royal and Sandwich terns were greatest for tarsus (K = 0.194 and K = 0.184, respectively), followed by mass (K = 0.143 and K = 0.164, respectively), and then wing cord (K = 0.125 and K = 0.110, respectively). Future studies evaluating causes of chick mortality would provide insight into the quality of habitat provided during this life stage. Chick growth rates may also be a useful indicator of ecological change and response to disturbances such as the Deepwater Horizon oil spill.

Barrier islands provide numerous ecosystem functions and services, including critical breeding habitat for many waterbird species. Louisiana's barrier islands are experiencing rapid land loss and habitat degradation. Restoration of barrier islands has become a high priority in Louisiana and barrier island degradation has increased waterbird reliance on restored dredge material islands. To improve restoration and management of barrier islands, we investigated the hatching success of Black Skimmer (Rynchops niger) and determined important habitat characteristics for their hatching success. Nest monitoring and nest habitat characteristics were measured at breeding colonies on the Isles Dernieres Barrier Island Refuge, Louisiana, in 2009 and 2010. Hatching success varied greatly for Black Skimmers (1–84%). Predation, flooding, and competition were the three main causes of nest failure. Habitat modeling identified nest elevation relative to the high-tide line and distance to high-tide line as important habitat characteristics. Continued restoration to build landmass on the islands is necessary to maintain quality nesting areas for Black Skimmers. Additionally, dredge applications to increase elevation, vegetation management, and predator control can provide more quality habitat and increase hatching success.

Gull-billed Terns (Gelochelidon nilotica) have historically demonstrated variability in nest-site selection and reproductive success throughout their breeding range. However, few studies have investigated the breeding parameters of Gull-billed Tern populations on barrier islands in the northern Gulf of Mexico, USA. The main objective of this study was to investigate annual variability of breeding population size, hatching success, and causes of nest failure during eight breeding seasons (2009–2016). Annual variation was observed in colony sizes (Range = 1–68 nests), colony locations (among five islands), and hatching success (0–93%). Mean hatching success was 56% and flooding was the main cause of failure, accounting for 64% of all failed nests. Additionally, nest site habitat characteristics were compared between successful and unsuccessful Gull-billed Tern nests. Nest substrate composition differed between successful and failed nests, and successful nests were also associated with higher elevation, greater distance from the high tide line, and less vegetative cover. There was considerable variation in Gull-billed Tern breeding population size and hatching success, which may be attributable to the dynamic nature of barrier island habitats. Long-term monitoring is required to better understand the breeding dynamics of Gull-billed Terns, but conservation efforts should consider maintaining island habitats that are protected from flooding and have adequate nesting substrate, minimal vegetation, and limited disturbance from humans and predators.

Response of breeding waterbird communities to the effects of hurricanes remains poorly understood. The impact of two 2008 hurricanes on the breeding waterbird community was investigated at the Isles Dernieres Barrier Island Refuge in southern Louisiana using pre- and post-hurricane survey data. After the 2008 hurricanes, the breeding community was reduced from 44,042 breeding pairs in 2008 to 27,977 pairs in 2009 and to 23,544 pairs in 2010. Populations of the five most abundant species, Brown Pelican (Pelecanus occidentalis), Laughing Gull (Leucophaeus atricilla), Royal Tern (Thallasseus maximus), Sandwich Tern (Thallasseus sandvincensis), and Black Skimmer (Rynchops niger), decreased from 2008 to 2010. In contrast, populations of Roseate Spoonbill (Platalea ajaja), Sooty Tern (Onychoprion fuscatus), and Gull-billed Tern (Gelochelidon nilotica) increased from 2008 to 2009 but declined in 2010. The dramatic decline of total breeding pairs in the year following hurricanes demonstrates the vulnerability of this community to tropical storms and habitat degradation. Further investigations of this community are necessary to understand how major disturbances affect resilience and long-term viability of colonial waterbird communities on barrier islands.

En 1845, la disparition de sir John Franklin et de son équipage dans l’Arctique canadien a engendré la plus grande opération de sauvetage de l’histoire de l’exploration. Plus de 30 expéditions de secours ont été envoyées en 20 ans, afin de découvrir le mystérieux destin de l’expédition Franklin qui visait à cartographier l’Arctique canadien et, par le fait même, le passage du Nord-Ouest. Les recherches se sont poursuivies d’ailleurs au 20e et au 21e siècle. Le 9 septembre 2014, on annonce que l’un des navires de l'expédition, plus tard identifié comme étant le HMS Erebus, a été retrouvé au large de l'île du Roi-Guillaume. Le 12 septembre 2016, une équipe de l’Arctic Research Foundation annonce qu’elle a retrouvé le Terror dans la baie Terror au Nunavut, au nord de l’endroit où on a découvert l’Erebus.