Mark L Mallory

Acadia University · Department of Biology

Long-range atmospheric transport of pollutants is generally assumed to be the main vector for arctic contamination, because local pollution sources are rare. We show that arctic seabirds, which occupy high trophic levels in marine food webs, are the dominant vectors for the transport of marine-derived contaminants to coastal ponds. The sediments of...

Marine plastic ingestion by seabirds was first documented in the 1960s, but over 50 years later our understanding about the prevalence, intensity, and subsequent effect of plastic pollution in the oceans is still developing. In Canada, systematic assessments using recognized standard protocols began only in the mid-2000s. With marine plastic pollut...

Reproductive timing in many taxa plays a key role in determining breeding productivity ¹, and is often sensitive to climatic conditions ² . Current climate change may alter the timing of breeding at different rates across trophic levels, potentially resulting in temporal mismatch between the resource requirements of predators and their prey ³ . Thi...

Ecological “big data” Human activities are rapidly altering the natural world. Nowhere is this more evident, perhaps, than in the Arctic, yet this region remains one of the most remote and difficult to study. Researchers have increasingly relied on animal tracking data in these regions to understand individual species' responses, but if we want to...

Plastic pollution is a ubiquitous global environmental problem. Plastic ingestion by seabirds is an increasing issue even in remote areas, such as the Arctic, yet research and monitoring of plastic ingestion in Arctic seabird populations is limited, and there are large knowledge gaps for many geographic regions. There is currently no standard techn...

Mercury (Hg) is a naturally-occurring, toxic contaminant that accumulates in ecosystems, potentially having deleterious effects on the health of wildlife and habitat quality. Significant advances have been made in understanding Hg cycling in freshwater and marine ecosystems, but the processes controlling Hg accumulation in bogs and the confounding...

American herring gulls (Larus smithsoniansus; hereafter herring gulls) are widely distributed, common seabirds with generalist diets. As is the case for many large gull species, herring gulls exploit human-altered landscapes for feeding and breeding, and these synanthropic birds can create a suite of human–bird conflict situations, ranging from mil...

An understanding of the geological history and ecosystems evolution of Big Meadow Bog peatland at Brier Island, Nova Scotia is an important element of informing the conservation management of critical habitats for a complex of nationally listed, rare, disjunct wetland species. The ecology of the peatland is influenced by both chemistry and morpholo...

Big Meadow Bog, in the center of Brier Island, Nova Scotia, has long been the nesting site for American herring gulls (Larus smithsoniansus Coues), with recent counts of approximately 3000 pairs of birds at the colony in the summer. Gulls move from the colony to fish-processing plants, mink farms, aquaculture sites, and marine coastlines to feed, a...

Considerable amounts of polyethylene terephthalate (PET) microplastic fibers are released into the environment by the laundering of polyester clothing. Microplastic fibers can be ingested by organisms in the environment. Therefore, it has been suggested that microplastic fibers act as vectors for adsorbed contaminants, which are subsequently desorb...

Microplastics have been found across the globe in the habitats of many amphibians. To investigate how exposure to microplastics affects hatching success, survival, growth, and development of wood frogs (Rana sylvatica), as well as how these animals may act as vectors for microplastics, a 96-day outdoor mesocosm experiment was conducted at the Queen...

In Canada, two federal departments have responsibilities relevant to fisheries bycatch: Environment and Climate Change Canada manages seabird populations, while Fisheries and Oceans Canada manages fisheries. Both departments need to determine population-level impacts of fisheries on seabirds to fulfill respective mandates, but gaps in policy implem...

Plastic pollution is omnipresent in the marine environment, including much of the Arctic. Northern fulmars (Fulmarus glacialis) are particularly vulnerable to ingesting plastics floating on the water's surface, and are an international biomonitor of this contaminant. We sampled plastic ≥1 mm in size from the stomachs of fulmars collected by Inuit h...

Incidental catch of seabirds (bycatch) in fisheries has been identified as a major threat to the conservation of seabird populations globally. Acquiring accurate, detailed data on seabird bycatch is an ongoing challenge to effective integrated ecosystem management of commercial fisheries. This is especially true in the Arctic region where different...

Ammospiza nelsoni subvirgata (Acadian subspecies of Nelson’s Sparrow) breeds in saltmarshes from northern Massachusetts to New Brunswick and eastern Quebec. In the Canadian Maritimes, this subspecies also successfully breeds in diked agricultural lands (i.e., “dikeland”) that were originally created by Acadian settlers in the 1600s. Little is known...

Aim Ecologically similar species living in sympatry are expected to segregate to reduce the effects of competition where resources are limiting. Segregation from heterospecifics commonly occurs in space, but it is often unknown whether such segregation has underlying environmental causes. Indeed, species could segregate because of different fundame...

Arctic biodiversity is under threat from both climate-induced environmental change and anthropogenic activity. However, the rapid rate of change and the challenging conditions for studying Arctic environments mean that many research questions must be answered before we can strategically allocate resources for management. Addressing threats to biodi...

Temporal variation in resource availability, physiological demands, and other factors are associated with many phenotypic changes in organisms. For example, there are often predictable stages of atrophy and hypertrophy in animals’ organs to accommodate changes in diet. Timing of stages may differ by sex given differences in life histories (e.g., eg...

Systematic surveys of marine birds from ships were first conducted by the Canadian Wildlife Service in Atlantic Canada in 1965, and then expanded to the Canadian Arctic in 1969 under PIROP (Programme intégré de recherches sur les oiseaux pélagiques). PIROP surveys ended in 1992, then resumed in 2006 under the Eastern Canada Seabirds at Sea program...

Migratory seabirds move across ocean basins and are one of the primary reservoirs of low pathogenic avian influenza virus (LPAIV). This includes the millions of thick-billed murres (Uria lomvia) and common murres (Uria aalge) that are distributed across northern hemisphere oceans. In response to increasingly frequent detections of highly pathogenic...

Several species of loons (or divers; Gaviidae) breed in Arctic Canada, and concern has been raised about their changes in abundance in light of threats such as bycatch and at-sea industrial development. These loons are not well monitored, but we gathered localized count data for three Arctic-nesting loons (Pacific loon Gavia pacifica, red-throated...

Alteration and diminution in sea ice cover in the Arctic region will give rise to an intensification and expansion of fishing activities in the Arctic and associated marginal seas. Increased fishing activity, especially in the summer, could pose a direct threat to the millions of seabirds breeding in this region, as well as non-breeding migrants, a...

In a warming Arctic, circumpolar long‐term monitoring programs are key to advancing ecological knowledge and informing environmental policies. Calls for better involvement of Arctic peoples in all stages of the monitoring process are widespread, although such transformation of Arctic science is still in its infancy. Seabirds stand out as ecological...

In a warming Arctic, circumpolar long-term monitoring programs are key to advancing ecological knowledge and informing environmental policies. Calls for better involvement of Arctic peoples in all stages of the monitoring process are widespread, although such transformation of Arctic science is still in its infancy. Seabirds stand out as ecological...

First detected in Atlantic Canada in December 2021, highly pathogenic avian influenza virus (HPAIV) subtype H5N1 clade 2.3.4.4b, A/Goose/Guangdong/1/96 lineage, has caused massive mortality in wild birds and domestic poultry in North America. Swallows (Hirundinidae), abundant in North American agricultural ecosystems, have been proposed as possible...

The ivory gull (Pagophila eburnea Phipps 1774) is a rare seabird found in the Canadian High Arctic. The Seymour Island Migratory Bird Sanctuary has supported the core colony for ivory gull research since the 1970s, but by the 2000s, survey work was extended across the species’ range in Nunavut, prompted by growing Indigenous concerns of population...

Rehabilitation and release back to the wild of orphaned American black bear (Ursus americanus) cubs is a wildlife management option used across North America. We reviewed the literature and surveyed wildlife managers and biologists within North America from August 2022 through March 2023 to gather information on their policies and practices regardi...

Birds are widely used as indicators of environmental contamination because they integrate signals across space and time. However, this advantage also means that locating the source of pollution can be challenging, especially for species that migrate large distances. Historically, the assignment of contaminant burden to particular life stages or loc...

The research station at Prince Leopold Island (PLI), initiated in 1975, was the first seabird monitoring site created in the Canadian Arctic. The island supports 150 000 breeding pairs of seabirds, principally thick-billed murres (Uria lomvia Linnaeus 1758), black-legged kittiwakes (Rissa tridactyla Linnaeus 1758) and northern fulmars (Fulmarus gla...

A controlled chamber method using continuous gold trap atomic fluorescence spectroscopy (AFS) (Tekran 2537X) for the analysis of Hg(0) emissions from moderate mass rock samples was developed and tested. A series of black shale and other bedrock samples from Nova Scotia, Canada, were used to test the method and its reproducibility. Hg(0) emissions a...

The Nasaruvaalik Island field station in the high Arctic was established to facilitate research and monitoring on rare seabird species, largely to meet regulatory obligations defined in Canada’s Species At Risk Act. After building a small research facility at the site, investigations have not only shed new insights on at-risk seabirds, but have: 1)...

North America's scoter species are poorly monitored relative to other waterfowl. Black Melanitta americana, surf M. perspicillata, and white‐winged M. deglandi scoter abundance and trend estimates are thus uncertain in many parts of these species' ranges. The most extensive source of waterfowl abundance and distribution data in North America is the...

The American Common Eider (Somateria mollisima dresseri) winters along the eastern coasts of the northern U.S. and southern Canada. Various lines of evidence indicate recent localized changes in eider abundance, particularly in the Gulf of Maine, where the most dramatic oceanic changes in the Northwest Atlantic are also underway. A range-wide overv...

Anthropogenic food subsidies attract opportunistic generalists like gulls in high densities, which may lead to negative impacts on human communities and local ecosystems. Managing impacts requires understanding why gulls use particular natural or industrial sites at different times of day or phases of the breeding cycle. Use of natural and human‐in...

Sea ice plays a fundamental role in Arctic marine environments, by driving primary productivity and sustaining ice-associated ecosystems. Simultaneously, sea ice influences the contamination of Arctic marine organisms, by modifying contaminant cycles or their bioavailability. Changes in sea ice conditions could therefore profoundly impact the funct...

A Eurasian lineage highly pathogenic avian influenza virus (HPAIV) of the clade 2.3.4.4b (Goose/Guangdong lineage) was detected in migratory bird populations in North America in December 2021, and it, along with its reassortants, have since caused wild and domestic bird outbreaks across the continent. Relative to previous outbreaks, HPAIV cases amo...

Conspecific brood parasitism (CBP) is an alternative reproductive tactic observed in at least 50% of waterfowl species. The effects of CBP on host fitness are not fully understood in most species, so it remains generally unknown whether the behaviour is a truly parasitic interaction with fitness benefits to the parasite and costs to the host. We st...

The American common eider (Somateria mollissima dresseri) is a colonially nesting sea duck breeding on islands in the coastal regions of Atlantic Canada. Declines in colony size have been pronounced in some parts of its range, notably in Nova Scotia, and may be attributable to a variety of interconnected factors including changes in habitat conditi...

Plastic pollution is distributed patchily around the world’s oceans. Likewise, marine organisms that are vulnerable to plastic ingestion or entanglement have uneven distributions. Understanding where wildlife encounters plastic is crucial for targeting research and mitigation. Oceanic seabirds, particularly petrels, frequently ingest plastic, are h...

Plastic pollution is ubiquitous, and the Arctic is no exception. One important step to understand the extent of the problem, and to monitor its impact is to have repeatable, comparable, and relevant measures across time and space that allow for the detection of marine litter trends. Arctic shorelines are a critical part of monitoring efforts. Pan-A...

In the Arctic, chemical contaminants, shipping, oil pollution, plastic pollution, changing habitats in relation to climate change and fisheries have been identified as environmental stressors to seabirds such as Fulmarus glacialis (northern fulmar; qaqulluk; ᖃᖁᓪᓗᖅ), but rarely have these stressors been considered within a cumulative effects framewo...

2023. Experts' opinions on threats to Leach's Storm-Petrels (Hydrobates leucorhous) across their global range. Avian Conservation and Ecology 18(1):11. https://doi. ABSTRACT. Seabirds are declining globally, though the threats they face differ among and within species and populations. Following substantial population declines at several breeding co...

Microplastics contaminate environments worldwide and are ingested by numerous species, whose health is affected in multiple ways. A key dimension of health that may be affected is the gut microbiome, but these effects are relatively unexplored. Here, we investigated if microplastics are associated with changes in proventricular and cloacal microbio...

Seabirds are globally recognized vectors of marine-derived materials, which get deposited on land at their breeding colonies, potentially altering local soil chemistry. We studied mercury (Hg) in soil cores on two islands in west Iceland that host thousands of nesting seabirds, predicting that Hg subsidies from nesting birds would result in elevate...

The eastern population of harlequin duck Histrionicus histrionicus in Canada has been designated a species of special concern since 2001 and as endangered from 1991 to 2001, largely due to low and declining wintering numbers detected in the 1980s. Our objectives were to summarize the current state of knowledge of harlequin duck abundance and distri...

The common snipe (Gallinago gallinago) is a wader that breeds in subarctic regions from Iceland to Russia, and for which global populations are in decline. We studied snipe breeding in western Iceland between 1998 and 2020, locating nests and ringing birds annually. In 2019 and 2020, we deployed geolocators on nesting adults to estimate the timing...

Global climate change is causing abiotic shifts such as higher air and ocean temperatures and disappearing sea ice in Arctic ecosystems. These changes influence Arctic-breeding seabird foraging ecology by altering prey availability and selection, affecting individual body condition, reproductive success, and exposure to contaminants such as mercury...

Studies on mercury bioaccumulation and biomagnification in coastal invertebrates in eastern Canada are limited, but these data are necessary to determine risk of mercury exposure effects in upper trophic level organisms. We quantified methylmercury (MeHg), total mercury (THg), and stable isotopes of δ13C and δ15N in 14 species of invertebrates in t...

Due to their natural geochemistry, intertidal estuarine ecosystems are vulnerable to bioaccumulation of methylmercury (MeHg), a neurotoxin that readily bioaccumulates in organisms. Determining MeHg concentrations in intertidal invertebrates at the base of the food web is crucial in determining MeHg exposure in higher trophic level organisms like fi...

Environmental impact assessments (EIAs) aim to assess the predicted effects of future projects on the environment, human health, and the economic potential of a region. They are an instrumental tool for sustainable development and to reduce the impact of large-scale industrial projects on biodiversity. The accurate assessment of the effects of proj...

Cadmium (Cd) is a trace element of toxicological concern that has been monitored in marine birds inhabiting the Canadian Arctic since 1975. Despite nearly 50 years of monitoring, research to date has largely evaluated single species, locations, or time points, and there is as of yet no holistic overview that jointly considers all available Cd data....

Mercury (Hg) is a globally distributed heavy metal, with negative effects on wildlife. Its most toxic form, methylmercury (MeHg), predominates in aquatic systems. Levels of MeHg in marine predators can vary widely among individuals and populations. Leach's storm-petrels (Hydrobates leucorhous) have elevated levels of Hg but the role of Hg in storm-...

Ultraviolet (UV) absorbents and industrial antioxidants are contaminants of emerging concern (CECs), but little is known about their distribution in Arctic wildlife, as well as how these contaminants vary over time, across regions, and between species. We used archived egg samples to examine the temporal patterns of 26 UV absorbents and industrial...

Mercury (Hg) is globally-distributed, with severe toxic effects on wildlife. Methylmercury biomagnifies within food webs, so long-lived, top predators such as seabirds are prone to high mercury concentrations. We synthesized historical and contemporary data on mercury concentrations in seabirds from the North Atlantic. We collected 614 values deter...

Conservation of mobile organisms is difficult in the absence of detailed information about movement and habitat use. While the miniaturization of tracking devices has eased the collection of such information, it remains logistically and financially difficult to track a wide range of species across a large geographic scale. Predictive distribution m...