Oceanites Inc.

Chevy Chase, MD, United States

Oceanites Inc.

Chevy Chase, MD, United States
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Lynch H.J.,University of Maryland University College | Crosbie K.,International Association of Antarctica Tour Operators | Fagan W.F.,University of Maryland University College | Naveen R.,Oceanites Inc.
Antarctic Science | Year: 2010

Commercial, shipborne tourism along the Antarctic Peninsula grew exponentially between 1989-90 and 2007-08, raising concern about the impact such activity may have on the environment of the region. Previous analyses of Antarctic tourism have focused narrowly on patterns of visitation and potential impacts at terrestrial landing sites. Here, using 19 years of passenger landing statistics and five years of reconstructed ship itineraries, we explore patterns of tourism activities in the Antarctic Peninsula region using a spatially explicit network theory analysis of ship itineraries. We find that passenger landings and marine traffic are highly concentrated at a few specific locations and that growth in tourism activity occurred disproportionally rapidly at these sites relative to growth in visitation of the Peninsula as a whole. We conclude by discussing the pros and cons of spatially concentrated tourism activity and the associated implications for ecosystem management. © 2009 Antarctic Science Ltd.

Lynch H.J.,State University of New York at Stony Brook | White R.,Oceanites Inc. | Black A.D.,Government of South Georgia and the South Sandwich Islands | Naveen R.,Oceanites Inc.
Polar Biology | Year: 2012

Due to its high spatial resolution, broad spatial coverage, and cost-effectiveness, commercial satellite imagery is rapidly becoming a key component of biological monitoring in the Antarctic. While considerable success in surveying emperor penguins (Aptenodytes forsteri) has been facilitated by their large size and the visual simplicity of their habitat, there has been considerably less progress in mapping colonies on the Antarctic Peninsula and associated sub-Antarctic islands where smaller penguin species breed on topographically complex terrain composed of mixed substrates. Here, we demonstrate that Adélie penguin (Pygoscelis adeliae), chinstrap penguin (P. antarcticus), gentoo penguin (P. papua), and macaroni penguin (Eudyptes chrysolophus) colonies can be detected by high-resolution (2-m multispectral, 40-50-cm panchromatic) satellite imagery and that under ideal conditions, such imagery is capable of distinguishing among groups of species where they breed contiguously. To demonstrate the potential for satellite imagery to estimate penguin population abundance, we use satellite imagery of Paulet Island (63°35′S, 55°47′W) to estimate a site-wide population of 115,673 (99,222-127,203) breeding pairs of Adélie penguins. © 2012 Springer-Verlag.

Clucas G.V.,University of Southampton | Dunn M.J.,British Antarctic Survey | Dyke G.,University of Southampton | Emslie S.D.,University of North Carolina at Wilmington | And 5 more authors.
Scientific Reports | Year: 2014

Climate change is a major threat to global biodiversity. Antarctic ecosystems are no exception. Investigating past species responses to climatic events can distinguish natural from anthropogenic impacts. Climate change produces 'winners', species that benefit from these events and 'losers', species that decline or become extinct. Using molecular techniques, we assess the demographic history and population structure of Pygoscelis penguins in the Scotia Arc related to climate warming after the Last Glacial Maximum (LGM). All three pygoscelid penguins responded positively to post-LGM warming by expanding from glacial refugia, with those breeding at higher latitudes expanding most. Northern (Pygoscelis papua papua) and Southern (Pygoscelis papua ellsworthii) gentoo sub-species likely diverged during the LGM. Comparing historical responses with the literature on current trends, we see Southern gentoo penguins are responding to current warming as they did during post-LGM warming, expanding their range southwards. Conversely, Adélie and chinstrap penguins are experiencing a 'reversal of fortunes' as they are now declining in the Antarctic Peninsula, the opposite of their response to post-LGM warming. This suggests current climate warming has decoupled historic population responses in the Antarctic Peninsula, favoring generalist gentoo penguins as climate change 'winners' while Adélie and chinstrap penguins have become climate change 'losers'.

Casanovas P.,Oceanites Inc. | Naveen R.,Oceanites Inc. | Forrest S.,Oceanites Inc. | Poncet J.,Golden Fleece Expedition Cruises | Lynch H.J.,State University of New York at Stony Brook
Polar Biology | Year: 2015

Seabirds along the western Antarctic Peninsula are known to be shifting in abundance and distribution in response to changing sea ice and prey distributions, but the spatial extent of these changes has remained an open question because survey efforts have focused on the more easily accessed northern coastline. We used a yacht-based field expedition (January 5–21, 2013) to complete the first comprehensive penguin (Pygoscelis spp.) and blue-eyed shag (Phalacrocorax [atriceps] bransfieldensis) population survey of the Graham and Loubet Coasts of the western Antarctic Peninsula since the mid-1980s. Our surveys document a sharp transition zone at the northern boundary of Marguerite Bay; north of this boundary zone, we confirm widespread declines in Adélie penguins and increasing populations of gentoo penguins, but south of this zone we find Adélie populations that have remained stable or increased in abundance since the previous surveys by Poncet and Poncet (Br Antarct Surv Bull 77:109–129, 1987). Marguerite Bay has long been known as a predator “hotspot,” but our findings suggest that Marguerite Bay has actually been improving for marine predators for at least several decades. Marguerite Bay, which has fundamentally different ocean dynamics than in areas just outside Marguerite Bay, has maintained persistent phytoplankton blooms over the past decade even as summer sea ice extent, which can inhibit access to breeding areas, has declined. This provides further support for the hypothesis that ocean productivity and sea ice dynamics are critical factors regulating Adélie penguin abundance in the region and that Marguerite Bay is now at the front lines of ecological change in this region. © 2015, Springer-Verlag Berlin Heidelberg.

Lynch H.J.,State University of New York at Stony Brook | Naveen R.,Oceanites Inc. | Trathan P.N.,British Antarctic Survey | Fagan W.F.,University of Maryland University College
Ecology | Year: 2012

As important marine mesopredators and sensitive indicators of Antarctic ecosystem change, penguins have been a major focus of long-term biological research in the Antarctic. However, the vast majority of such studies have been constrained by logistics and relate mostly to the temporal dynamics of individual breeding populations from which regional trends have been inferred, often without regard for the complex spatial heterogeneity of population processes and the underlying environmental conditions. Integrating diverse census data from 70 breeding sites across 31 years in a robust, hierarchical analysis, we find that trends from intensely studied populations may poorly reflect regional dynamics and confuse interpretation of environmental drivers. Results from integrated analyses confirm that Pygoscelis adeliae (Adé lie Penguins) are decreasing at almost all locations on the Antarctic Peninsula. Results also resolve previously contradictory studies and unambiguously establish that P. antarctica (Chinstrap Penguins), thought to benefit from decreasing sea ice, are instead declining regionally. In contrast, another open-water species, P. papua (Gentoo Penguin), is increasing in abundance and expanding southward. These disparate population trends accord with recent mechanistic hypotheses of biological change in the Southern Ocean and highlight limitations of the influential but oversimplified "sea ice" hypothesis. Aggregating population data at the regional scale also allows us to quantify rates of regional population change in a way not previously possible. © 2012 by the Ecological Society of America.

Lynch H.J.,University of Maryland University College | Lynch H.J.,State University of New York at Stony Brook | Fagan W.F.,University of Maryland University College | Naveen R.,Oceanites Inc. | And 2 more authors.
Marine Ecology Progress Series | Year: 2012

Numerous studies link climate change with advancing breeding phenology in birds, but less frequently considered are the joint impacts on sympatrically breeding communities of birds. We used data on clutch initiation dates (CID) from 4 sites along the Western Antarctic Peninsula for 3 congeneric and sympatrically breeding penguin species (Adélie Pygoscelis adeliae, gentoo P. papua and chinstrap P. antarcticus) to understand what factors correlate with the phenology and synchrony of breeding and how these factors might change with the recent warming experienced in this region. We found that clutch initiation was most significantly correlated with October air temperatures such that all 3 species advanced clutch initiation to varying degrees in warmer years. Gentoo penguins were able to advance CID almost twice as much (3.2 d °C-1) as Adélie (1.7 d °C-1) and chinstrap penguins (1.8 d °C-1). Beyond the variation explained by mean October temperatures, there was an unexplained trend to earlier clutch initiation of 0.15 ± 0.05 d yr-1. Greater plasticity in gentoo breeding phenology compressed the mean interval between Adélie and gentoo breeding in warm years and this may increase competition for nesting space in mixed colonies. Our results suggest that differential responses in breeding phenology to changing temperatures represent an additional mechanism by which climate change may affect competitive interactions and, consequently, pygoscelid penguins on the Antarctic Peninsula. © Inter-Research 2012.

Lynch H.J.,University of Maryland University College | Lynch H.J.,Oceanites Inc. | Fagan W.F.,University of Maryland University College | Naveen R.,Oceanites Inc.
Polar Biology | Year: 2010

Petermann Island (65°10′S, 64°10′W), one of the Antarctic Peninsula's most frequently visited locations, is at the epicenter of a rapid shift in which an Adélie penguin dominated fauna is becoming gentoo penguin dominated. Over the course of five seasons, the breeding productivity of Adélie and gentoo penguins breeding at Petermann Island were monitored to identify drivers of this rapid community change. The impact of tourist visitation on breeding success was also investigated. Consistent with larger trends in this region, the Adélie penguin population decreased by 29% and the gentoo penguin population increased by 27% between the 2003/2004 and 2007/2008 seasons. Reproductive success among Adélie penguins ranged from 1.09 to 1.32 crèched chicks/nest, which was higher than or comparable to other sites and is an unlikely explanation for the precipitous decline of Adélie penguins at Petermann Island. Whereas gentoo penguin reproductive success was lowest in colonies frequently visited by tourists, Adélie penguin colonies frequently visited by tourists had higher reproductive success than those visited only occasionally. These results are placed in the context of other studies on reproductive success and the impact of tourist visitation on breeding colonies of Adélie and gentoo penguins. © 2009 Springer-Verlag.

Naveen R.,Oceanites Inc. | Lynch H.J.,State University of New York at Stony Brook | Forrest S.,Oceanites Inc. | Mueller T.,Biodiversity and Climate Research Center | Polito M.,University of North Carolina at Wilmington
Polar Biology | Year: 2012

Deception Island (62°57′S, 60°38′W) is one of the most frequently visited locations in Antarctica, prompting speculation that tourism may have a negative impact on the island's breeding chinstrap penguins (Pygoscelis antarctica). Discussions regarding appropriate management of Deception Island and its largest penguin colony at Baily Head have thus far operated in the absence of concrete information regarding the current size of the penguin population at Deception Island or long-term changes in abundance. In the first ever field census of individual penguin nests at Deception Island (December 2-14, 2011), we find 79,849 breeding pairs of chinstrap penguins, including 50,408 breeding pairs at Baily Head and 19,177 breeding pairs at Vapour Col. Our field census, combined with a simulation designed to capture uncertainty in an earlier population estimate by Shuford and Spear (Br Antarct Surv Bull 81:19-30, 1988), suggests a significant (>50 %) decline in the abundance of chinstraps breeding at Baily Head since 1986/1987. A comparative analysis of high-resolution satellite imagery for the 2002/2003 and the 2009/2010 seasons suggests a 39 % (95th percentile CI = 6-71 %) decline (from 85,473 ± 23,352 to 52,372 ± 14,309 breeding pairs) over that 7-year period and provides independent confirmation of population decline in the abundance of breeding chinstrap penguins at Baily Head. The decline in chinstrap penguins at Baily Head is consistent with declines in this species throughout the region, including sites that receive little or no tourism; as a consequence of regional environmental changes that currently represent the dominant influence on penguin dynamics, we cannot ascribe any direct link between chinstrap declines and tourism from this study. © 2012 Springer-Verlag.

Brasso R.L.,University of North Carolina at Wilmington | Polito M.J.,University of North Carolina at Wilmington | Lynch H.J.,State University of New York at Stony Brook | Naveen R.,Oceanites Inc. | Emslie S.D.,University of North Carolina at Wilmington
Science of the Total Environment | Year: 2012

Remote regions such as the Antarctic have become increasingly important for investigations into far-reaching anthropogenic impacts on the environment, most recently in regard to the global mercury cycle. Spatial patterns of mercury availability in four regions of the Antarctic Peninsula were investigated using three species of sympatrically breeding Pygoscelis penguins as biomonitors. Eggshells with intact membranes from Adélie, Gentoo, and Chinstrap penguins were collected at 24 breeding colonies in the South Orkney Islands, South Shetland Islands, eastern Antarctic Peninsula, and western Antarctic Peninsula during the 2006/2007 austral summer. In addition, we compared eggshell membrane mercury concentrations with eggshell stable isotope values (δ15N and δ13C) to determine if species-specific trophic or foraging habitat preferences influenced female mercury exposure prior to breeding. With few exceptions, mercury concentrations were found to be fairly homogeneous throughout the Antarctic Peninsula suggesting little spatial variation in the risk of exposure to dietary mercury in this food web. Mercury concentrations in Gentoo and Adélie penguins were similar while Chinstrap penguins tended to have higher eggshell membrane mercury concentrations than their congeners. However, inter and intra-specific differences in eggshell membrane mercury concentration were not related to eggshell δ15N or δ13C values, a likely result of all three species foraging at similar trophic positions. The lack of regional-scale differences in mercury availability in this marine ecosystem may be a reflection of generally uniform atmospheric deposition and upwelling of regionally homogeneous deep water rather than from geographically distinct point sources. © 2012 Elsevier B.V.

Polito M.J.,University of North Carolina at Wilmington | Lynch H.J.,University of Maryland University College | Naveen R.,Oceanites Inc. | Emslie S.D.,University of North Carolina at Wilmington
Marine Ecology Progress Series | Year: 2011

While the foraging ecology of the Adélie penguin Pygoscelis adeliae and gentoo penguin P papua has been well studied, little is known on the distribution and diet of these species outside the breeding season In the present study we used stable carbon (δ13C) and nitrogen (d15N) isotope analyses of eggshells to examine the pre-breeding diets and foraging habitats of female Adélie and gentoo penguins from 23 breeding colonies along the eastern and western Antarctic Peninsula (AP), South Shetland Islands, and South Orkney Islands, in 2006 Adélie penguin eggshells from the eastern AP, South Shetland Islands, and South Orkney Islands shared similar isotopic signatures and were significantly lower in both δ13C and δ15N values than eggshells from birds breeding along the western AP This result suggests that Adélie penguin populations that are geographically separated during the breeding season by the Adélie 'gap,' a 400 km region in the western AP devoid of breeding Adélie penguins, also inhabit geographically distinct habitats during the late winter prior to the breeding season To a lesser degree, gentoo penguin eggshell isotope values also varied across breeding colonies, which likely reflects local scale variation in their near-shore foraging grounds Furthermore, unlike the breeding period when krill (primarily Euphausia superba) dominates penguin diets in these regions, our findings suggest that fish and/or other high trophic-level prey species comprise a significant portion (468 to 629%) of female Adélie and gentoo penguin diets prior to breeding © Inter-Research 2011.

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