Carcass Removal Research Articles

Magnitude and correlates of bird collisions at glass bus shelters in an urban landscape.

Wildlife residing in urban landscapes face many human-related threats to their survival. For birds, collision with glass on manmade structures has been identified as a major hazard, causing hundreds of millions of avian fatalities in North America every year. Although research has investigated factors associated with bird-glass collision mortality at buildings, no prior studies have focused on bird fatalities at glass-walled bus shelters. Our objectives in this study were to describe the magnitude of bird-bus shelter collisions in the city of Stillwater, Oklahoma and assess potential predictors of collision risk, including characteristics of shelters (glass area) and surrounding land cover (e.g., vegetative features). We surveyed for bird carcasses and indirect collision evidence at 18 bus shelters over a five-month period. Linear regression and model selection results revealed that the amount of glass on shelters and the area of lawn within 50 m of shelters were both positively related to fatal bird collisions; glass area was also positively associated with observations of collision evidence on glass surfaces. After accounting for scavenger removal of carcasses, we estimate that a minimum of 34 birds are killed each year between May and September by collision with the 36 bus shelters in the city of Stillwater. While our study provides an initial look at bird fatalities at bus shelters, additional research is needed to generate a large-scale estimate of collision mortality and to assess species composition of fatalities at a national scale. Designing new bus shelters to include less glass and retrofitting existing shelters to increase visibility of glass to birds will likely reduce fatal bird collisions at bus shelters and thus reduce the cumulative magnitude of anthropogenic impacts to birds in cities.

Testing for errors in estimating bird mortality rates at wind farms and power lines

SummaryWind power, as an alternative to fossil fuels, is increasingly common, and is expanding worldwide. Wind farms cause mortality of flying animals through collision with moving rotor blades, and from electrocution on associated power lines. Avian mortality rates have been estimated from birds collected under turbines over varying time intervals. However, without adequate and frequent monitoring, dead birds may be removed by scavengers and thus cause an underestimation of fatalities. In this paper, we tested experimentally for possible errors arising in avian mortality caused by the removal of carcasses by scavengers. At two different wind farms and associated power lines in southern Spain, we placed pigeon and quail carcasses to determine their disappearance rate. All dead pigeons were radio-tagged to estimate distances taken by scavengers. We found significant differences in carcass disappearance rates of pigeons and quails, and between wind farms and power lines but not between habitats. All quails and 45% of pigeon carcasses had disappeared by the third and fourteenth day, respectively. Less than half (40%) of the carcasses were found < 100 m from where they were deposited. While scavenging losses may vary according to the location of the wind farm or power line, here we propose a method to estimate correctly the number of fatalities at any wind farm and power line. Using this method, we can improve our understanding of the real impact of wind structures on adjacent bird communities, and adopt appropriate measures to ensure their conservation.

Ecological role of vertebrate scavengers in urban ecosystems in the UK.

Recent research has demonstrated how scavenging, the act of consuming dead animals, plays a key role in ecosystem structure, functioning, and stability. A growing number of studies suggest that vertebrate scavengers also provide key ecosystem services, the benefits humans gain from the natural world, particularly in the removal of carcasses from the environment. An increasing proportion of the human population is now residing in cities and towns, many of which, despite being highly altered environments, contain significant wildlife populations, and so animal carcasses. Indeed, non‐predation fatalities may be higher within urban than natural environments. Despite this, the fate of carcasses in urban environments and the role vertebrate scavengers play in their removal have not been determined. In this study, we quantify the role of vertebrate scavengers in urban environments in three towns in the UK. Using experimentally deployed rat carcasses and rapid fire motion‐triggered cameras, we determined which species were scavenging and how removal of carcass biomass was partitioned between them. Of the 63 experimental carcasses deployed, vertebrate scavenger activity was detected at 67%. There was a significantly greater depletion in carcass biomass in the presence (mean loss of 194 g) than absence (mean loss of 14 g) of scavengers. Scavenger activity was restricted to three species, Carrion crows Corvus corone, Eurasian magpies Pica pica, and European red foxes Vulpes vulpes. From behavioral analysis, we estimated that a maximum of 73% of the carcass biomass was removed by vertebrate scavengers. Despite having low species richness, the urban scavenger community in our urban study system removed a similar proportion of carcasses to those reported in more pristine environments. Vertebrate scavengers are providing a key urban ecosystem service in terms of carcass removal. This service is, however, often overlooked, and the species that provide it are among some of the most disliked and persecuted.

Estimates of avian collision with power lines and carcass disappearance across differing environments

AbstractData on collisions of birds with high‐voltage electric power lines are scarce and are often gathered without protocols for the correction of carcass disappearance. There is actually growing awareness that it is important to accomplish carcass removal trials in order to develop correction factors for producing adjusted estimates of mortality due to collisions. In this study, we provided for the first time raw counts and estimates of bird collisions across seven Italian areas that largely differ in their habitats. We also carried out carcass removal trials to compute the rate of carcass disappearance and produce better estimates of collision events and of optimal time intervals of carcass searches. Results of 1‐year monitoring showed a general low frequency of birds collided with the power lines. Carcass removal trials showed effects of carcass size and season on the carcass disappearance, which varied largely among the study areas. In four areas, both small and large carcasses had more than 50% probability to be removed within 3–5 days from their distribution. Given the high variation among study areas, we suggest that estimates of carcass persistence and optimal time intervals should be conducted concurrently for each new study site.

Key role in ecosystem functioning of scavengers reliant on a single common species.

The importance of species richness in maintaining ecosystem function in the field remains unclear. Recent studies however have suggested that in some systems functionality is maintained by a few abundant species. Here we determine this relationship by quantifying the species responsible for a key ecosystem role, carcass removal by scavengers. We find that, unlike those within largely unaltered environments, the scavenger community within our highly altered system is dominated by a single species, the Carrion crow, despite the presence of a number of other scavenging species. Furthermore, we find no relationship between abundance of crows and carcass removal. However, the overall activity of crows predicts carcass biomass removal rate in an asymptotic manner, suggesting that a relatively low level of abundance and scavenging activity is required to maintain this component of ecosystem function.

The detectability and persistence of road-killed butterflies: An experimental study

Estimates of detectability and removal of carcasses have been determined for vertebrates but not for invertebrates, although the latter are more frequently killed on roads. The aim of this study was to estimate the detectability and persistence of road-killed butterflies and to assess the relative contributions of the location on the road, volume of traffic, and presence of scavengers to the removal of dead butterflies. During three independent experiments, dead butterflies from 12 species were placed at randomly chosen locations along selected road sections (both on asphalt and on a verge) with varying vehicle traffic volume (including sections without vehicles) and scavenger abundance. Dead butterflies were counted, scavengers' behaviour was observed, and the traffic volume was measured. The detectability was higher for butterflies placed on asphalt (0.979) than on a verge (0.767) and increased with body size. The removal rate of dead butterflies from asphalt on roads with vehicles was four times faster (persistence probability of 12h: 0.139) than on roads where vehicles were absent (persistence probability: 0.508). Overall, only 5% of butterflies persisted for a 48-h period. Vehicles and bird scavengers removed 14.9% and 9.6% of dead butterflies, respectively. The probability of dead butterfly removal by birds was positively correlated with traffic, indicating that the number of road-killed butterflies might be substantially underestimated on roads with high traffic. This shows that imperfect detection should be taken into account when estimating the number of road-killed butterflies, especially for butterflies on road verges.

Roles of Raptors in a Changing World: From Flagships to Providers of Key Ecosystem Services

Birds of prey have been, in comparison to other avian groups, an uncommon study model, mainly due to the limitations imposed by their conservative life strategy (low population density and turnover). Nonetheless, they have attracted a strong interest from the point of view of conservation biology because many populations have been close to extinction and because of their recognised role in ecosystems as top predators and scavengers and as flagship species. Today, after more than a century of persecution, and with the exception of some vultures still very much affected by illegal poisoning, many populations of birds of prey have experienced significant recoveries in many regions of Spain and the European Mediterranean. These changes pose new challenges when addressing the conservation of raptors in the coming decades. On this basis, and from a preferentially Mediterranean perspective, we have focused our attention on the need of describing and quantifying the role of these birds as providers of both regulating (rodent pest control and removal of livestock carcasses) and cultural ecosystem services. Moreover, we revisited persisting conflicts with human interests (predation of game species) and call attention to the emergence of new conflicts with a strong social and media component such as the predation on live cattle by vultures. Also, the rampant humanization of the environment determines the need for new solutions to the growing, yet scarcely explored, problem of accidents in new infrastructures such as mortality in wind farms. Finally, we explored in depth the ecological response of birds of prey to large-scale habitat changes such as urbanisation and abandonment of marginal lands that are also expected to increase in the near future. We urgently need more scientific knowledge to provide adequate responses to the challenge of keeping healthy populations of avian predators and scavengers in a rapidly changing world.

Potential threat to Eurasian griffon vultures in Spain from veterinary use of the drug diclofenac

Summary Spain holds > 95% of the European breeding population of the Eurasian griffon vulture Gyps fulvus. Vultures provide important ecosystem services in carcass removal and influence emissions of greenhouse gases. Despite the known toxicity of the non‐steroidal anti‐inflammatory drug diclofenac to this species and other Gyps vultures, in March 2013 the Agencia Española de Medicamentos y Productos Sanitarios (AEMPS) approved the use of two medicines containing diclofenac for veterinary use in horses, pigs and cattle in Spain. To assess the potential impact of medicated ungulate carcasses on Eurasian griffon vulture populations in Spain, we first used information on the metabolism and elimination of diclofenac from medicated cattle and pigs to calculate residue levels in relation to time elapsed between dosing and death. Secondly, probabilities of the death of a vulture per meal were calculated based upon experimental studies of diclofenac toxicity. Finally, annual numbers of vulture deaths expected to be caused by diclofenac were obtained by multiplying the death rates per meal by the estimated numbers of vulture meals taken from expected numbers of medicated carcasses suggested by AEMPS. Assuming that vultures feed on carcasses that were treated with diclofenac 8 h before the animal's death, the annual number of vulture deaths caused by diclofenac was estimated at 715–6389, depending upon the estimate of numbers of medicated carcasses assumed and the version of the dose–response model used. Using a density‐independent simulation model of a vulture population, the expected rate of decline of the Spanish population of Eurasian griffon vultures caused by these deaths is 0·9–7·7% per year. A density‐dependent simulation model also indicated substantial population‐level effects. Formal estimates of precision and sensitivity analyses of effects of unmeasured variables highlight the uncertainty of estimates using currently available data. Synthesis and applications. Due to the possibility of causing an important impact on vulture populations, our findings justify a precautionary ban on the veterinary use of diclofenac in Spain and encourage the use of meloxicam, a vulture‐safe alternative drug. A programme of monitoring of non‐steroidal anti‐inflammatory drug contamination of ungulate carcasses available to vultures and of moribund and dead obligate and facultative avian scavengers would be needed to be confident that a damaging level of contamination is not present.

Genotype Analysis of Bacillus anthracis Strains Circulating in Bangladesh.

In Bangladesh, anthrax, caused by the bacterium Bacillus anthracis, is considered an endemic disease affecting ruminants with sporadic zoonotic occurrences in humans. Due to the lack of knowledge about risks from an incorrect removal of infected carcasses, the disease is not properly monitored, and because of the socio-economic conditions, the situation is under-reported and under-diagnosed. For sensitive species, anthrax represents a fatal outcome with sudden death and sometimes bleeding from natural orifices. The most common source of infection for ruminants is ingestion of spores during grazing in contaminated pastures or through grass and water contaminated with anthrax spores. Domestic cattle, sheep and goats can also become infected through contaminated bone meal (used as feed) originating from anthrax-infected carcasses. The present investigation was conducted to isolate B. anthracis organisms from 169 samples (73 soil, 1 tissue, 4 bone and 91 bone meal samples) collected from 12 different districts of Bangladesh. The sampling was carried out from 2012 to 2015. Twelve samples resulted positive for B. anthracis. Biomolecular analyses were conducted starting from the Canonical Single Nucleotide Polymorphism (CanSNP) to analyze the phylogenetic origin of strains. The analysis of genotype, obtained through the Multiple Locus Variable Number Tandem Repeat Analysis (MLVA) with the analysis of 15 Variable Number Tandem Repeats (VNTR), demonstrated four different genotypes: two of them were previously identified in the district of Sirajganj. The sub-genotyping, conducted with Single Nucleotide Repeats analysis, revealed the presence of eight subgenotypes. The data of the present study concluded that there was no observed correlation between imported cattle feed and anthrax occurrence in Bangladesh and that the remarkable genetic variations of B. anthracis were found in the soil of numerous outbreaks in this country.

Carcass Type Affects Local Scavenger Guilds More than Habitat Connectivity.

Scavengers and decomposers provide an important ecosystem service by removing carrion from the environment. Scavenging and decomposition are known to be temperature-dependent, but less is known about other factors that might affect carrion removal. We conducted an experiment in which we manipulated combinations of patch connectivity and carcass type, and measured responses by local scavenger guilds along with aspects of carcass depletion. We conducted twelve, 1-month trials in which five raccoon (Procyon lotor), Virginia opossum (Didelphis virginiana), and domestic rabbit (Oryctolagus spp.) carcasses (180 trials total) were monitored using remote cameras in 21 forest patches in north-central Indiana, USA. Of 143 trials with complete data, we identified fifteen species of vertebrate scavengers divided evenly among mammalian (N = 8) and avian species (N = 7). Fourteen carcasses (9.8%) were completely consumed by invertebrates, vertebrates exhibited scavenging behavior at 125 carcasses (87.4%), and four carcasses (2.8%) remained unexploited. Among vertebrates, mammals scavenged 106 carcasses, birds scavenged 88 carcasses, and mammals and birds scavenged 69 carcasses. Contrary to our expectations, carcass type affected the assemblage of local scavenger guilds more than patch connectivity. However, neither carcass type nor connectivity explained variation in temporal measures of carcass removal. Interestingly, increasing richness of local vertebrate scavenger guilds contributed moderately to rates of carrion removal (≈6% per species increase in richness). We conclude that scavenger-specific differences in carrion utilization exist among carcass types and that reliable delivery of carrion removal as an ecosystem service may depend on robust vertebrate and invertebrate communities acting synergistically.

Factors Influencing Data Quality in Citizen Science Roadkill Projects

Factors Influencing Data Quality in Citizen Science Roadkill Projects

Use of bird carcass removals by urban scavengers to adjust bird-window collision estimates

Use of bird carcass removals by urban scavengers to adjust bird-window collision estimates

Impact of Wind Facilities on Bats in the Neotropics

We monitored the bat fatalities caused by a 13 turbines wind facility installed in western Puerto Rico (West Indies) over a period of 23 months. The post-construction monitoring includes observed fatalities and a corrected fatality estimate expressed as bats/ turbine/year adjusted for bat carcass removal rates, searcher efficiency, and percent area searched. Data on seasonality of fatalities and distance of carcasses from turbines is also provided. Eleven out of the 13 species of bats in Puerto Rico suffered fatalities, including all five species of phyllostomids. These were: Molossus molossus and Tadarida brasiliensis (Molossidae); Artibeus jamaicensis, Monophyllus redmani, Stenoderma rufum, Brachyphylla cavernarum and Erophylla bombifrons (Phyllostomidae); Noctilio leporinus (Noctilionidae); Eptesicus fuscus and Lasiurus minor (Vespertilionidae); and Mormoops blainvillei (Mormoopidae). This is one of the first published reports of the impact of wind turbines on bats in the Neotropics.

Functional replacement across species pools of vertebrate scavengers separated at a continental scale maintains an ecosystem function

Summary The composition of species pools can vary in space and time. While many studies are focused on understanding which factors influence the make‐up of species pools, the question to which degree biogeographic variation in species composition propagates to biogeographic variation in ecological function is rarely examined. If different local species assemblages operate in ways that maintain specific ecological processes across continents, they can be regarded as functionally equivalent. Alternatively, variation in species assemblages might result in the loss of ecological function if different species fulfil different functions, and thereby fail to maintain the ecological process. Here, we test whether ecological function is affected by differences in the composition of species pools across a continental scale, comparing a tropical with a temperate pool. The model systems are assemblages of vertebrates foraging on ocean beaches, and the ecological function of interest is the consumption of wave‐cast carrion, a pivotal process in sandy shore ecosystems. We placed fish carcasses (n = 179) at the beach–dune interface, monitored by motion‐triggered cameras to record scavengers and quantify the detection and removal of carrion. Scavenging function was measured on sandy beaches in two distinct biogeographic regions of Australia: tropical north Queensland and temperate Victoria. The composition of scavenging assemblages on sandy beaches varied significantly across the study domain. Raptors dominated in the tropics, while invasive red foxes were prominent in temperate assemblages. Notwithstanding the significant biogeographic change in species composition, ecological function – as indexed by carcass detection and removal – was maintained, suggesting strong functional replacement at the continental scale. Species pools of vertebrate scavengers that are assembled from taxonomically distinct groups (birds vs. mammals) and located in distinct climatic regions (temperate vs. tropical) can maintain an ecological process via replacement of species with comparable functional traits.

Invasive carnivores alter ecological function and enhance complementarity in scavenger assemblages on ocean beaches.

Species composition is expected to alter ecological function in assemblages if species traits differ strongly. Such effects are often large and persistent for nonnative carnivores invading islands. Alternatively, high similarity in traits within assemblages creates a degree of functional redundancy in ecosystems. Here we tested whether species turnover results in functional ecological equivalence or complementarity, and whether invasive carnivores on islands significantly alter such ecological function. The model system consisted of vertebrate scavengers (dominated by raptors) foraging on animal carcasses on ocean beaches on two Australian islands, one with and one without invasive red foxes (Vulpes vulpes). Partitioning of scavenging events among species, carcass removal rates, and detection speeds were quantified using camera traps baited with fish carcasses at the dune-beach interface. Complete segregation of temporal foraging niches between mammals (nocturnal) and birds (diurnal) reflects complementarity in carrion utilization. Conversely, functional redundancy exists within the bird guild where several species of raptors dominate carrion removal in a broadly similar way. As predicted, effects of red foxes were large. They substantially changed the nature and rate of the scavenging process in the system: (1) foxes consumed over half (55%) of all carrion available at night, compared with negligible mammalian foraging at night on the fox-free island, and (2) significant shifts in the composition of the scavenger assemblages consuming beach-cast carrion are the consequence of fox invasion at one island. Arguably, in the absence of other mammalian apex predators, the addition of red foxes creates a new dimension of functional complementarity in beach food webs. However, this functional complementarity added by foxes is neither benign nor neutral, as marine carrion subsidies to coastal red fox populations are likely to facilitate their persistence as exotic carnivores.

Scavenging of migratory bird carcasses in the Sonoran Desert

In this study we report avian and mammalian scavengers foraging on migratory bird carcasses in the Sonoran Desert. We used remote cameras to monitor carcasses we found along a power line right-of-way (n = 25). We documented four species scavenging 10 carcasses (kit fox, Vulpes macrotis, n = 4; coyote, Canis latrans, n = 3; common raven, Corvus corax, n = 2, and greater roadrunner, Geococcyx californianus, n = 1) and recorded coyote tracks at three additional carcasses. Neither remote cameras nor tracks indicated the scavenger species of the remaining carcasses. Our data suggest migrant birds might provide an important food source for resident scavengers, particularly in desert habitats where food can be scarce. Our study also supports prior assertions that failure to account for removal of carcasses by scavengers might cause errors in estimates of mortality.

Limited functional redundancy in vertebrate scavenger guilds fails to compensate for the loss of raptors from urbanized sandy beaches

AbstractAimGlobally, urbanization is one of the most widespread, intense and ecologically destructive forms of landscape transformation, and it is often concentrated in coastal areas. Theoretically, species losses attributable to urbanization are predicted not to alter overall ecosystem function if functional redundancy (i.e. replacement of function by alternative species) compensates for such losses. Here, we test this expectation by measuring how coastal urbanization affects scavenger guilds on sandy beaches and whether changes in guild composition result either in an overall loss of scavenging efficiency, or in functional compensation under alternative guild structures, maintaining net ecosystem functioning.LocationFourteen beaches along the east coast of Australia with variable levels of urbanization.MethodsScavenging communities and rates of carrion removal were determined using motion‐triggered cameras at the beach‐dune interface.ResultsA substantial shift in the community structure of vertebrate scavengers was associated with gradients in urbanization. Iconic and functionally important raptors declined precipitously in abundance on urban beaches. Importantly, other vertebrates usually associated with urban settings (e.g. dogs, foxes, corvids) did not functionally replace raptors. In areas where < 15% of the abutting land had been developed into urban areas, carcass removal by scavengers was often complete, but always > 70%. Conversely, on beaches bordering coastal cities with < 40% of natural vegetation remaining, two‐thirds of fish carcasses remained uneaten by scavengers. Raptors removed 70–100% of all deployed fish carcasses from beaches with < 8% urban land cover, but this number dropped significantly with greater levels of urbanization and was not compensated by other scavenger species in urban settings.Main conclusionsThere is limited functional redundancy in vertebrate scavenger communities of sandy beach ecosystems, which impacts the system's capacity to mitigate the ecological consequences of detrimental landscape transformations.

Proximate Analysis of Kijing Taiwan Carcass (Anodonta woodiana) in Wet and Dry Forms

Field practice activities conducted in laboratory incluiding the process of carcass removal from its shells was done in the Laboratory of Nutrition and Fish Feed Technology, and also analysis of Kijing Taiwan carcass chemical composition was done in the Research and Industrial Standardization Institute of Manado. The purpose of field practice are: Analyzing the Proximate composition, Vitamin C, Calcium, and Energy of Kijing Taiwan carcass taiwan in wet and dry form. Providing scientific information about the nutrient content of Kijing Taiwan in wet and dry form. Acquire skills in operating the Proximate instruments of Vitamin C, Calcium, and Energy in the laboratory. Based on the results of the Kijing Taiwan (Anodonta woodiana) carcass proximate analysis in wet form, the data showed, 11.59% of protein, 80.66% of water, 0.26% of fat, 3.06% of ash, 0.23% of crude fiber, 4.20% of carbohydrate, 65.5 kcal of energy, 0.59% of calcium, 3.86 mg/100 g of Vitamin C. While the dry form of the data showed, 54.84% of protein, 12.18% of water, 4.08% of fat, 14.92% of ash, 0.53% of crude fiber, 13.45% of carbohydrates, 309.88 kcal of energy, 0.55% of calcium, 14.88% of vitamin C mg/100 g. Keywords: Carcass, Anodonta woodiana, proximate analysis, vitamin C, calcium, and energy

Estimation of bird‐vehicle collision mortality on U.S. roads

ABSTRACTRoads have numerous direct and indirect ecological impacts on wildlife. Vehicle collisions are a top impact of roads on birds, with tens of millions of birds thought to be killed each year in the United States. However, currently available mortality estimates are extrapolated from a single study. We reviewed the literature and used 20 mortality rates extracted from 13 studies to systematically quantify data‐driven estimates of annual U.S. mortality from bird‐vehicle collisions. We generated 4 separate estimates along with uncertainty using different subsets of data deemed to be rigorous enough to contribute relatively little bias to estimates. All of our estimates of vehicle mortality are higher than previous U.S. figures. When averaging across model iterations, we estimated that between 89 and 340 million birds die annually from vehicle collisions on U.S. roads. Sensitivity analyses indicated that uncertainty about survey‐related biases (scavenger removal and searcher detection of carcasses) contributes the greatest amount of uncertainty to our mortality estimates. Future studies should account for these biases to provide more accurate local estimates of mortality rates and to inform more precise national mortality estimates. We found relatively little information available to quantify regional, seasonal, and taxonomic patterns of vehicle collision risk, and substantial uncertainty remains about whether collisions contribute to large‐scale impacts on bird populations. Nonetheless, the large magnitude of bird mortality caused by vehicle collisions combined with evidence that collisions can contribute to local population declines for some species highlights the need for implementation of conservation and management actions to reduce this mortality. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

Carrion decomposition causes large and lasting effects on soil amino acid and peptide flux

Carrion decomposition is a critical component of the biogeochemical cycling of energy and nutrients within the biosphere. Two important and currently overlooked nitrogen (N) pools likely to be affected by carrion are free amino acid (FAA) and peptide pools, which are a newly recognised point of competition between plants and microorganisms for the N resource. A carcass addition experiment was established using recently (<12 h) deceased kangaroo (Macropus giganteus) carcasses to quantify soil nutrient changes in a box gum grassy woodland ecosystem. Soil samples were taken every 12 weeks, and analysed for available nutrient content and FAA and peptide turnover rates. Carcasses were a source of N, adding an average of 4.4 kg m−2 to the soils directly under the decomposing carcasses in our study, representing a significant redistribution of this resource within the ecosystem. There was also a significant and lasting input of proteins (40 mg/kg) and amino acids (25 mg/kg) into the soil, which increased microbial turnover of these labile N compounds. Dissolved organic N (DON) cycling in rangelands and natural ecosystems is an overlooked part of the N and C cycle despite representing the most important nutrient input into these systems. Based on our results, we argue for a re-think on the removal of carcasses as an ecosystem management tool, as they provide large and lasting resource islands which influence soil N cycling.