Seven considerations about dingoes as biodiversity engineers: the socioecological niches of dogs in Australia

2012 ◽  
Vol 34 (1) ◽  
pp. 119 ◽  
Author(s):  
Peter J. S. Fleming ◽  
Benjamin L. Allen ◽  
Guy-Anthony Ballard

Australian dingoes have recently been suggested as a tool to aid biodiversity conservation through the reversal or prevention of trophic cascades and mesopredator release. However, at least seven ecological and sociological considerations must be addressed before dog populations are positively managed.Domestication and feralisation of dingoes have resulted in behavioural changes that continue to expose a broad range of native and introduced fauna to predation.Dingoes and other dogs are classic mesopredators, while humans are the apex predator and primary ecosystem engineers in Australia.Anthropogenic landscape changes could prevent modern dingoes from fulfilling their pre-European roles.Dingoes are known to exploit many of the same species they are often presumed to ‘protect’, predisposing them to present direct risks to many threatened species.The assertion that contemporary dog control facilitates the release of mesopredators disregards the realities of effective dog control, which simultaneously reduces fox and dog abundance and is unlikely to enable increases in fox abundance.The processes affecting threatened fauna are likely a combination of both top-down and bottom-up effects, which will not be solved or reversed by concentrating efforts on managing only predator effects.Most importantly, human social and economic niches are highly variable across the ecosystems where dingoes are present or proposed. Human perceptions will ultimately determine acceptance of positive dingo management.Outside of an adaptive management framework, positively managing dingoes while ignoring these seven considerations is unlikely to succeed in conserving native faunal biodiversity but is likely to have negative effects on ecological, social and economic values.

2020 ◽  
Vol 287 (1938) ◽  
pp. 20202202
Author(s):  
L. Mark Elbroch ◽  
Jake M. Ferguson ◽  
Howard Quigley ◽  
Derek Craighead ◽  
Daniel J. Thompson ◽  
...  

Top-down effects of apex predators are modulated by human impacts on community composition and species abundances. Consequently, research supporting top-down effects of apex predators occurs almost entirely within protected areas rather than the multi-use landscapes dominating modern ecosystems. Here, we developed an integrated population model to disentangle the concurrent contributions of a reintroduced apex predator, the grey wolf, human hunting and prey abundances on vital rates and abundance of a subordinate apex predator, the puma. Increasing wolf numbers had strong negative effects on puma fecundity, and subadult and adult survival. Puma survival was also influenced by density dependence. Overall, puma dynamics in our multi-use landscape were more strongly influenced by top-down forces exhibited by a reintroduced apex predator, than by human hunting or bottom-up forces (prey abundance) subsidized by humans. Quantitatively, the average annual impact of human hunting on equilibrium puma abundance was equivalent to the effects of 20 wolves. Historically, wolves may have limited pumas across North America and dictated puma scarcity in systems lacking sufficient refugia to mitigate the effects of competition.


2021 ◽  
Author(s):  
Daniel Roy Garrett ◽  
Fanie Pelletier ◽  
Dany Garant ◽  
Marc Bélisle

Climate change predicts the increased frequency, duration, and intensity of inclement weather periods, such as unseasonably low temperatures and prolonged precipitation. Many migratory species have advanced the phenology of important life history stages, and as a result are likely exposed to these periods of inclement spring weather more often, thus risking reduced fitness and population growth. For declining avian species, including aerial insectivores, anthropogenic landscape changes such as agricultural intensification are another driver of population declines. These landscape changes may affect the foraging ability of food provisioning parents, as well as reduce the probability a nestling will survive periods of inclement weather, through for example pesticide exposure impairing thermoregulation and punctual anorexia. Breeding in agro-intensive landscapes may thus exacerbate the negative effects of inclement weather under climate change. We used daily temperatures related to significant reductions of insect prey availability (cold snaps), combined with measures of precipitation, and assessed their impact on Tree Swallow (Tachycineta bicolor) fledging success, a declining aerial insectivore breeding across a gradient of agricultural intensification. Fledging success decreased with the number of cold snap days experienced by a brood, and this relationship was worsened during periods of prolonged precipitation. We further found the overall negative effects of experiencing periods of inclement weather are exacerbated in more agro-intensive landscapes. Our results indicate that two of the primary hypothesized drivers of many avian population declines may interact to further increase the rate of declines in certain landscape contexts.


2019 ◽  
Vol 286 (1897) ◽  
pp. 20182501 ◽  
Author(s):  
Rong Wang ◽  
Xiao-Yong Chen ◽  
Yan Chen ◽  
Gang Wang ◽  
Derek W. Dunn ◽  
...  

The collapse of mutualisms owing to anthropogenic changes is contributing to losses of biodiversity. Top predators can regulate biotic interactions between species at lower trophic levels and may contribute to the stability of such mutualisms, but they are particularly likely to be lost after disturbance of communities. We focused on the mutualism between the fig tree Ficus microcarpa and its host-specific pollinator fig wasp and compared the benefits accrued by the mutualists in natural and translocated areas of distribution. Parasitoids of the pollinator were rare or absent outside the natural range of the mutualists, where the relative benefits the mutualists gained from their interaction were changed significantly away from the plant's natural range owing to reduced seed production rather than increased numbers of pollinator offspring. Furthermore, in the absence of the negative effects of its parasitoids, we detected an oviposition range expansion by the pollinator, with the use of a wider range of ovules that could otherwise have generated seeds. Loss of top-down control has therefore resulted in a change in the balance of reciprocal benefits that underpins this obligate mutualism, emphasizing the value of maintaining food web complexity in the Anthropocene.


Author(s):  
Redmond R. Shamshiri ◽  
Muhammad Razif Mahadi ◽  
Kelly R. Thorp ◽  
Wan Ishak Wan Ismail ◽  
Desa Ahmad ◽  
...  

2009 ◽  
Vol 15 (3) ◽  
pp. 171 ◽  
Author(s):  
Peter B. McQuillan ◽  
James E.M. Watson ◽  
Nick B. Fitzgerald ◽  
David Leaman ◽  
David Obendorf

The continental island of Tasmania supports an extraordinary biota featuring ancient communities, high levels of endemism and many species extinct on mainland Australia. However, more than 670 species are currently listed as threatened, mainly due to changes in their habitat since European settlement. Although Tasmania has a relatively high proportion of its land in reserves with some degree of representation for most vegetation types, habitat protection in some bioregions is very low. In this paper we approach biodiversity assessment in Tasmania by (i) addressing critical, natural ecological processes that underpin and sustain its biodiversity, (ii) assessing the current trends in, and threats to, these processes, and (iii) identifying gaps in knowledge that limit the effective management of these processes for conservation. It is hoped that this will contribute a sound basis for ongoing adaptive management for biodiversity conservation in Tasmania and assist in re-focusing the purpose of the reserve network from representation to persistence of the native biota.


Marine Policy ◽  
2017 ◽  
Vol 76 ◽  
pp. 28-37 ◽  
Author(s):  
Gavin McDonald ◽  
Bill Harford ◽  
Alejandro Arrivillaga ◽  
Elizabeth A. Babcock ◽  
Ramon Carcamo ◽  
...  

2013 ◽  
Vol 35 (1) ◽  
pp. 15 ◽  
Author(s):  
Peter J. S. Fleming ◽  
Benjamin L. Allen ◽  
Guy-Anthony Ballard

Johnson and Ritchie (2012) have provided a criticism of our opinion piece (Fleming et al. 2012). There is some common ground, but we remain unconvinced by their view that our reasoning was unsound or beside the point. In this response, we discuss where Johnson and Ritchie have provided unconvincing evidence to refute our seven considerations, and reiterate and demonstrate why these considerations remain important. The mesopredator release or suppression hypothesis in Australian ecosystems must be objectively evaluated before positive management of dingoes and other free-ranging dogs is recommended or implemented. Adaptive comanagement of free-ranging dogs can be used for both biodiversity conservation and the mitigation of livestock predation but caution must be exercised when considering using free-ranging dogs as a conservation tool.


La Granja ◽  
2021 ◽  
Vol 35 (1) ◽  
Author(s):  
Sofía Crespo ◽  
Carlos Solórzano ◽  
Josè Guerrero-Casado

Illegal wildlife trafficking has negative effects on biodiversity conservation at both global and local scale. Therefore, the establishment of appropriate conservation measures requires local studies that quantify this problem. The objective of this work was to quantify and characterize the species of birds and mammals seized in the period 2016-2017, at the Valle Alto Wildlife Rescue Centre and Wildlife Refuge. The study showed that 212 specimens belonging to 41 different species were confiscated. More birds than mammals were confiscated, and a greater proportion of birds were included in a national and international threat category. A clear preference for primates, parrots and squirrels was found. Furthermore, the presence of species with a distribution range outside the study area revealed the existence of the transportation of species from other parts of the country. Although these data are only a sample of what is actually trafficked in the country, they provide an approach of the type of species that are illegally trafficked in this biodiversity hotspot.


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