Controls on atmospheric chloroiodomethane (CH2ClI) in marine environments

Mixing ratios of chloroiodomethane (CH2ClI) in ambient air were quantified in the coastal North Atlantic region (Thompson Farm, Durham, New Hampshire, and Appledore Island, Maine) and two remote Pacific areas (Christmas Island, Kiribati, and Oahu, Hawaii). Average mixing ratios were 0.15 ± 0.18 and 0.68 ± 0.66 parts per trillion by volume (pptv) at Thompson Farm and Appledore Island, respectively, compared to 0.10 ± 0.05 pptv at Christmas Island and 0.04 ± 0.02 pptv in Hawaii. Photolysis constrained the daytime mixing ratios of CH2ClI at all locations with the minimum occurring at 1600 local time. Daily average fluxes to the atmosphere were estimated from mixing ratios and loss due to photolysis at Appledore Island, Christmas Island and Hawaii, and were 58 ± 9, 19 ± 3, and 5.8 ± 1.0 nmol CH2ClI m−2 d−1, respectively. The measured sea‐to‐air flux from seawater equilibrator samples obtained near Appledore Island was 6.4 ± 2.9 nmol CH2ClI m−2 d−1. Mixing ratios of CH2ClI at Appledore Island increased with increasing wind speed. The maximum mixing ratios observed at Thompson Farm (1.6 pptv) and Appledore Island (3.4 pptv) are the highest reported values to date, and coincided with high winds associated with the passage of Tropical Storm Bonnie. We estimate that high winds during the 2004 hurricane season increased the flux of CH2ClI from the North Atlantic Ocean by 8 ± 2%

Evidence of chronic cadmium exposure identified in the critically endangered Christmas Island flying-fox (Pteropus natalis)

The Christmas Island flying-fox (Pteropus natalis) is the last native mammal on Christmas Island and its population is in decline. Phosphate mining occurs across much of the eastern side of Christmas Island. The phosphate deposits are naturally rich in cadmium, and potentially other metals, which may be threatening the Christmas Island flying-fox population. To test this, concentrations of metals (cadmium, copper, iron, mercury, lead, and zinc) were measured in fur and urine collected from Christmas Island flying-foxes and interpreted concurrently with urinalysis and serum biochemistry data. In addition, metal concentrations in liver and kidney samples from two Christmas Island flying-foxes and associated histological findings from one of these individuals are reported. Fur cadmium concentrations were significantly higher in the Christmas Island flying-fox compared to concentrations found in flying-foxes in mainland Australia. Additionally, 30% of Christmas Island flying-foxes had urine cadmium concentrations exceeding maximum concentrations previously reported in flying-foxes in mainland Australia. Glucosuria and proteinuria were identified in two Christmas Island flying-foxes, suggestive of renal dysfunction. In one aged flying-fox, kidney cadmium concentrations were four-fold higher than toxic thresholds reported for domestic mammals. Microscopic evaluation of this individual identified bone lesions consistent with those described in laboratory animals with chronic cadmium poisoning. These results suggest that Christmas Island flying-foxes are being exposed to cadmium and identification of these sources is recommended as a focus of future research. Unexpectedly, urine iron concentrations in Christmas Island flying-foxes were higher compared to previous studies of Australian mainland flying-foxes, which suggests that urinary excretion of iron may be an important aspect of iron homeostasis in this species whose diet is iron rich

Gastrointestinal parasites of feral cats from Christmas Island

Objective To investigate the gastrointestinal parasites present in feral cats on Christmas Island, with particular interest in the protozoan parasite Toxoplasma gondii. Procedure Faecal and serum samples were collected from 28 and 25 cats respectively that were trapped as part of an ongoing eradication program being run on Christmas Island by the Department of Environment and Conservation. Faecal samples were screened microscopically for helminth and protozoan parasites. Serum samples were screened for antibodies to T gondii using a commercial indirect immunofluorescence assay (IFA) and a latex agglutination test (LAT). Results The most common helminth parasites detected were Toxocara cati (present in 15 of 28 faecal samples), Strongyloides sp (13/28), Aelurostrongylus abstrusus, (7/28), an unidentified capillarid (6/28) and Ancylostoma sp (4/28). Based on serology, T gondii was the most common parasite detected (protozoan or otherwise) with antibodies detected in 24 serum samples by IFA and 23 serum samples by LAT. Conclusion Cats on Christmas Island harbour many of the helminth and protozoan parasites reported from feral cats elsewhere in Australia. The high seroprevalence of T gondii in these cats indicates a high level of exposure to the parasite in this environment

The NOAA TOGA antenna array

The Aeronomy Laboratory recently installed a 100 x 100 meter array antenna with limited beam steering on Christmas Island as a part of the TOGA (Tropical Ocean and Global Atmosphere) program. The array and the associated beam steering and indicating hardware are described

Christmas Island: A question of self-determination

The notion of self-determination for Christmas Island has been considered for many years. There have been a range of reports, studies, inquiries and indeed protests (on the Island and in Canberra) over the years that have failed to provide a solution which is satisfactory to residents of Christmas Island and Australia’s Commonwealth Government. Accordingly, the purpose of this thesis is to explore and investigate the possibilities and options of the Territory of Christmas Island: a) becoming an autonomous self-governing region (Parliamentary Legislative Assembly); b) being incorporated into the legislative arrangements of West Australia (WA) or Northern Territory (NT); c) developing an alternative mixed delivery model of governance, incorporating elements from the above options (such as an ‘internal territory arrangement’); or d) maintaining the status quo. The thesis will discuss and examine the principles of democratic governance, including responsible government and representative democracy. It will also consider the unique history, culture and demography of Christmas Island, as well as the financial arrangements underpinning the existing governance model. It will discuss land tenure and asset ownership, which are both contentious issues on the island. Finally, the various future governance options will be examined, with a view to considering whether how effectively they might work within the Christmas Island context. The thesis utilises a range of reports and submissions made on the issue during parliamentary inquiries, as well as contemporary literature on self-determination and governance

Invasive animals and the Island Syndrome: Parasites of feral cats and black rats from Western Australia and its offshore islands

Introduced animals impact ecosystems due to predation, competition and disease transmission. The effect of introduced infectious disease on wildlife populations is particularly pronounced on islands where parasite populations are characterised by increased intensity, infra-community richness and prevalence (the “Island Syndrome”). This thesis studied parasite and bacterial pathogens of conservation and zoonotic importance in feral cats from two islands (Christmas Island, Dirk Hartog Island) and one mainland location (southwest Western Australia), and in black rats from Christmas Island. The general hypothesis tested was that Island Syndrome increases the risk of transmission of parasitic and bacterial diseases introduced/harboured by cats and rats to wildlife and human communities. To investigate the Island Syndrome, necropsies were performed on feral cats and black rats and the macro parasites identified were collected and quantified to ascertain parasite prevalence, infra-community richness and intensity. On Christmas Island, it was determined that 92% of feral cats and 84% of rats harboured helminth parasites with an infra-community richness of 0-6, and 0-7, species in cats and rats, respectively. A high intensity (number of individual parasites recovered per host) was observed for some parasite species. These findings demonstrated that three epidemiological characteristics (high prevalence, infra-community richness and intensity/abundance) conformed to the characteristics of the Island Syndrome. However, contrary to the Island Syndrome hypothesis, a high regional richness of parasites was observed on Christmas Island, with nine species of helminth recorded in cats and 10 species in rats). The parasite community characteristic observations were repeated on Dirk Hartog Island, which also exhibited the same three characteristics of Island Syndrome (high prevalence, infra-community richness and intensity/abundance), but where no difference in regional richness was observed compared with the mainland environment. Specifically, the overall prevalence was significantly higher (p≤0.01) on Dirk Hartog Island (100%) compared to southwest WA (79.6%), as was mean infra-community richness (p≤0.001) (3.61±1.41 on Dirk Hartog Island and 1.57±1.29 from southwest WA). For those parasite species occurring on Dirk Hartog Island and in southwest WA, the prevalence and abundance was found to be significantly higher on Dirk Hartog Island than the southwest WA (p≤0.019 and p≤0.003, respectively). These findings suggest that not all facets proposed by the Island Syndrome hypothesis apply to all island environments, particularly for parasite communities harboured by invasive species. Parasites of both zoonotic and conservation significance were detected in the cats and rats from both islands and from mainland Western Australia. Pathogenic bacteria of public health importance were identified; two species of Bartonella in rats (Bartonella phoceensis and an unidentified Bartonella species) on Christmas Island, two species Bartonella in cats (B. henselae and B. koehlerae) from southwest Western Australia, and Leptospira interrogans from both cats and rats on Christmas Island. The presence of Trypanosoma in cats and rats (from all three locations) and Leishmania (Christmas Island only) were investigated, with neither of these vector-borne protozoans identified at any of the locations. In summary, this thesis presents new data pertaining to parasite community structures in two invasive mammalian pest species of global importance following their introduction to islands, and the potential relationship between their parasite community structures and parasite biology, prevailing physiographic factors and faunal biology. The observations suggest that cats and rats are important in contributing to and maintaining artificially elevated parasite species’ richness within both insular and mainland environments. The findings also highlight potential threats that invasive animals pose with respect to disease transmission to susceptible ecological communities, in particular insular ecosystems, as reservoir hosts for parasitic and bacterial organisms

The passage of authority: imagining the political transformation of Australia’s Christmas Island, from sovereignty to governance

In 2012, Australia’s Christmas Island is best known as an island of immigration detention, a key component of Australia’s growing offshore border security apparatus, where interdicted boat arrivals seeking asylum are detained and processed. This article offers one account of how the Island came to be what it is, by providing two snapshots of the operable set of power relations on Christmas Island, then and now: ‘Island in the Sun’, and ‘Tropics of Governance’. Side by side, their stark contrast reveals the passage of authority through time and place, from the embodied, unified voice of the sovereignty of the British Empire to the palliative communication and bureaucratic sincerity that characterise governance. By disclosing shifting patterns of emergence and decay and showing border security’s intimate relation to governance, this article seeks to offer a deepened understanding of the current detention situation in its immanence. What can now be seen as Christmas Island’s past follies also reveals the restless work of successive political imaginations, the shifting ways and means by which an island can be translated into a solution to a political problem, and how successive solutions tend toward wreck and ruin

Collateral Damage: The impact of Australian asylum seeker policy on Christmas Islanders (2001-2011)

Since the Tampa incident in 2001, Christmas Island has been a central site where Australia’s border protection and asylum seeker policies are visible This article takes four key events over a ten year period to track the impact on Christmas Islanders and on the Islanders’ changing attitudes towards asylum seekers, detention and federal government policies. The views of Christmas Islanders are not often heard in public discourse about detention on the island. This article seeks to provide a platform for a snapshot of views and to call for a greater role for Islanders in decisions that profoundly affect their lives

Australian asylum policy: the Tampa effect

On 26 August 2001 a Norwegian freighter, the MV Tampa, rescued 433 asylum seekers from their vessel the KM Palapa 1 that was in distress in the stretch of ocean between Christmas Island and the coast of Indonesia. At the insistence of the rescued passengers, the captain of the Tampa asked the Australian government for permission to land them on Christmas Island — a request that was refused. There followed a week-long standoff while the world watched the drama unfold