Making a new dog?

Authors: Thomas M Newsome, Peter J S Fleming, Christopher R Dickman, Tim S Doherty, William J Ripple, Euan G Ritchie, and Aaron J Wirsing

Published in: BioScience (early view)

Abstract

We are in the middle of a period of rapid and substantial environmental change. One impact of this upheaval is increasing contact between humans and other animals, including wildlife that take advantage of anthropogenic foods. As a result of increased interaction, the evolution and function of many species may be altered through time via processes including domestication and hybridization, potentially leading to speciation events.

We discuss the ecological and management importance of such possibilities, using gray wolves and other large carnivores as case studies.

Image caption: A hypothetical comparison of gray wolf (Canis lupus) ecological effects in wilderness areas (left) and human-modified systems (right) where there are abundant anthropogenic foods.

We identify five main ways that carnivores might be affected: changes to social structures, behavior and movement patterns, changes in survivorship across wild- to human-dominated environments, evolutionary divergence, and potential speciation.

As the human population continues to grow and urban areas expand while some large carnivore species reoccupy parts of their former distributions, there will be important implications for human welfare and conservation policy.

Thomas M Newsome, Peter J S Fleming, Christopher R Dickman, Tim S Doherty, William J Ripple, Euan G Ritchie, Aaron J Wirsing (2017) Making a New Dog? BioScience PDF DOI

 

The Conversation: Government needs to front up billions, not millions, to save Australia’s threatened species

By Don Driscoll (Deakin University) Bek Christensen (University of Queensland) and Euan Ritchie (Deakin University)

Southern cassowaries, orange-bellied parrots, Leadbeater’s possums, and Australia’s only purple wattle are among the threatened species the government is seeking conservation investment for under its recently released threatened species prospectus. The prospectus seeks business and philanthropic support in partnership with the government and community groups to raise around A$14 million each year.

Orange-bellied parrots are one of the species included in the government’s Threatened Species Prospectus. Image crdeit: JJ Harrison via Wikimedia Commons

The government has proposed 51 projects, costing from A$45,000 to A$6 million. At first glance the prospectus is a positive initiative.

But it also highlights that the current government is unwilling to invest what’s needed to assure the conservation of our threatened plants, animals and other organisms.

The good news

The government’s partial outsourcing of conservation investment and responsibility might have some benefit. Raising broader awareness about the plight of Australia’s threatened species, particularly among Australia’s leading companies and donors, could lead to valuable conservation gains. It could translate to pressure for greater financial investment in conservation and less damaging actions by big companies.

The prospectus includes an excellent range of critically important projects. These include seed banks for plants facing extinction, and projects to control feral animals and create safe havens for mammals and birds.

These projects could help to save species on the brink of extinction, such as the critically endangered Gilbert’s potoroo, the Christmas Island flying fox and the orange-bellied parrot.

The projects have a high chance of success. Community groups and government are already on board and ready to take action, if only the funds materialise.

Why do so many species need urgent help?

The State of the Environment Report released in early March shows that the major pressures on wildlife have not decreased since 2011 when the previous report was released. The prospects for most threatened species have not improved.

Habitat loss is still the biggest threat. The homes of many threatened species are continually under threat from developments. Coal mines threaten the black-throated finch, urban sprawl eats away at the last 1% of critically endangered Victorian grasslands, and clearing for agriculture has spiked in Queensland.

Feral animals are widespread and control programs have been inadequate. New diseases are emerging, such as the chytrid fungus that has devastated frog populations worldwide.

The horticulture industry, for example, introduced myrtle rust to Australia. The disease was poorly managed when it was first detected. It now infects more than 350 species of the Myrtaceae family (including eucalypts).

We have so many threatened species because national and state governments don’t invest enough money in protecting our natural heritage, and environmental protections have been rolled back in favour of economic development.

Show us the money

Over the past three years the federal government has invested A$210 million in threatened species. This annual investment of A$70 million each year is minuscule compared with the government’s revenue (0.017% of A$416.9 billion).

It includes projects under the National Landcare Program, Green Army (much of which didn’t help threatened species) and the 20 Million Trees program.

The A$14 million that the prospectus hopes to raise is a near-negligible proportion of annual revenue (0.003%).

Globally, the amount of money needed to prevent extinctions and recover threatened species is at least ten times more than what is being spent.

In Australia, A$40 million each year would prevent the loss of 45 mammals, birds and reptiles from the Kimberley region.

Can we afford it? The 2016 Defence White Paper outlines an expansion of Australia’s defence expenditure from A$32.4 billion in 2016-17 to A$58.7 billion by 2025, even though the appropriate level of investment is extremely uncertain.

We are more certain that our biodiversity will continue to decline with current funding levels. Every State of the Environment report shows ongoing biodiversity loss at relatively stable, low-level funding.

And what will happen if industry won’t open its wallets? Will the government close the funding gap, or shrug its shoulders, hoping the delay between committing a species to extinction and the actual event will be long enough to avoid accountability?

In the past few years we’ve seen the extinction of the Christmas Island forest skink, the Christmas Island pipistrelle, and the Bramble Cay melomys with no public inquiry. Academics have been left to probe the causes, and there is no clear line of government responsibility or mechanism to provide enough funding to help prevent more extinctions.

Popularity poll

Another problem is the prospectus’s bias towards the cute and cuddly, reflecting the prejudice in the Commonwealth Threatened Species Strategy. The strategy and prospectus make the assumption that potential benefactors are inclined to fork out for a freckled duck, but not for a Fitzroy land snail.

The prospectus includes almost half of Australia’s threatened mammals (listed under the Environment Protection and Biodiversity Conservation Act) and one-fifth of the threatened birds.

Other groups are woefully represented, ranging from 13% of threatened reptiles to just 1% of threatened plants and none of the listed threatened invertebrates. The prospectus does not even mention spectacular and uniquely Australian threatened crayfish, snails, velvet worms, beetles, butterflies, moths and other insects.

The allocation of funds is equally problematic. We found that birds received the most money (A$209,000 per species on average), followed by mammals and plants.

Raising new funds to help save iconic species is valuable, and can help other species. This focus on birds and mammals wouldn’t be a problem if the government were to pick up the tab for the less popular threatened species.

But it hasn’t. That means our threatened species program will continue to be exceptionally biased, while many more species vanish forever, with little acknowledgement.

We think that the prospectus, despite its biases, is a positive initiative. It is vital to engage society, including business and wealthy philanthropists, in the care of Australia’s natural heritage. But it also highlights how little the government is willing to invest in preserving our threatened wildlife and ecosystems.

This article was originally published on The Conversation. Read the original article, including reader comments.

The Conversation

The Conversation

Responses of invasive predators and native prey to a prescribed forest fire

Authors: Bronwyn A Hradsky, Craig Mildwaters, Euan G Ritchie, Fiona Christie, and Julian Di Stefano

Published in: Journal of Mammalogy (early view)

Abstract

Fire shapes biome distribution and community composition worldwide, and is extensively used as a management tool in flammable landscapes. There is growing concern, however, that fire could increase the vulnerability of native fauna to invasive predators.

We developed a conceptual model of the ways in which fire could influence predator–prey dynamics.

Using a before–after, control–impact experiment, we then investigated the short-term effects of a prescribed fire on 2 globally significant invasive mesopredators (red fox, Vulpes vulpes, and feral cat, Felis catus) and their native mammalian prey in a fire-prone forest of southeastern Australia. We deployed motion-sensing cameras to assess species occurrence, collected predator scats to quantify diet and prey choice, and measured vegetation cover before and after fire. We examined the effects of the fire at the scale of the burn block (1,190 ha), and compared burned forest to unburned refuges.

Pre-fire, invasive predators and large native herbivores were more likely to occur at sites with an open understory, whereas the occurrence of most small- and medium-sized native mammals was positively associated with understory cover. Fire reduced understory cover by more than 80%, and resulted in a 5-fold increase in the occurrence of invasive predators. Concurrently, relative consumption of medium-sized native mammals by foxes doubled, and selection of long-nosed bandicoots (Perameles nasuta) and short-beaked echidnas (Tachyglossus aculeatus) by foxes increased. Occurrence of bush rats (Rattus fuscipes) declined. It was unclear if fire also affected the occurrence of bandicoots or echidnas, as changes coincided with normal seasonal variations.

Overall, prescribed fire promoted invasive predators, while disadvantaging their medium-sized native mammalian prey. Further replication and longer-term experiments are needed before these findings can be generalized. Nonetheless, such interactions could pose a serious threat to vulnerable species such as critical weight range mammals. Integrated invasive predator and fire management are recommended to improve biodiversity conservation in flammable ecosystems.

Hradsky BA, Mildwaters C, Ritchie EG, Christie F, Di Stefano J (2017) Responses of invasive predators and native prey to a prescribed forest fire, Journal of Mammalogy PDF DOI

Communication: Science censorship is a global issue

Authors: Euan G Ritchie, Don A Driscoll and Martine Maron

Published in: Nature, volume 542, number 7640 (February 2017)

Government gagging of scientists is a slippery slope towards removing evidence from public debate.

Government gagging of scientists is a slippery slope towards removing evidence from public debate.

President Donald Trump issued an order on 23 January to effectively gag US government scientists at the Environmental Protection Agency and the Department of Agriculture from communicating with the media and the public (see Nature 54210112017). Regrettably, suppression of public scientific information is already the norm, or is being attempted, in many countries (see, for example, go.nature.com/2kr5dnd). We fear that such gagging orders could encourage senior bureaucrats to use funding as a tool with which to rein in academic freedoms.

In Australia, public servants must abide by codes of conduct for communication that restrict them from contributing scientific evidence to public debates. Allegations emerged in 2011 that an Australian state government had threatened to stop funding university scientists who spoke out against cattle grazing in national parks, despite peer-reviewed evidence that this could damage a fragile alpine ecosystem and was unlikely to reduce fire risk as claimed (see also Nature 4714222011).

The response of scientists to this type of coercion has been to share scientific information widely and openly using such legal means as social media to defend facts and transparency (see Nature 5414352017). Academics and scientific associations are among the last still free to speak, so must continue to do so to protect open discussion of government policies.

Ritchie EG, Driscoll DA, Maron M (2017) Communication: Science censorship is a global issue, Nature 542 PDF DOI 

The case for a dingo reintroduction in Australia remains strong: a reply to Morgan et al., 2016

Authors: Thomas M Newsome, Aaron C Greenville, Mike Letnic, Euan G Ritchie and Christopher R Dickman

Published in: Food Webs (early view)

dingofootprint

We challenge the arguments of Morgan et al. in regard to the efficacy of dingo reintroductions Image credit: Daryll Bellingham via Flickr

In their paper “Trophic cascades and dingoes in Australia: does the Yellowstone wolf-elk- willow model apply?” Morgan et al. (2016) argue that the case for dingo reintroduction in Australia, based on trophic cascade theory, is “weak”. They conclude that, “because of climate instability, the strong top-down trophic responses reported from the Yellowstone National Park case study are unlikely to apply in arid and semi-arid south-eastern Australia and are speculative at best”.

We agree that dingoes (Canis dingo) are likely to exert different effects on ecological communities in Australia as compared to grey wolves (Canis lupus) in North America. A comparison of body sizes and dietary preferences between these canid species alludes to their functional ecological differences. Differences in the biological communities and climate between Yellowstone National Park and Australia also prevent direct comparisons of trophic cascade-processes between the two regions. These facts should not, however, preclude examination of the efficacy and consequences of dingo reintroductions in Australia.

We contend that Morgan et al. (2016):

  1. misunderstand the circumstances that make trophic cascades important to consider in Australia,
  2. do not acknowledge key reasons why dingo reintroduction has been proposed,
  3. haven’t recognised the different pathways by which dingoes could influence ecosystems via trophic cascades, and
  4. do not fully acknowledge literature and theory relevant to understanding the interplay of bottom-up and top-down processes in Australia.

Our reply is intended to assist managers and decision makers when deciding whether or not to reintroduce dingoes into Australian ecosystems.

Newsome TM, Greenville AC, Letnic M, Ritchie EG, Dickman CR (2017) The case for a dingo reintroduction in Australia remains strong: A reply to Morgan et al., 2016, Food Webs, PDF DOI

ABC Radio: Has roo meat made it to your dinner table?

Roo meat. Image credit Wikimedia Commons

Kangaroo meat. Image credit Wikimedia Commons

What are you throwing into the trolley as you wander through the meat section at the supermarket? Beef? Lamb? Chicken?

I spoke to ABC’s Gillian O’Shaughnessy about why we should consider eating kangaroo meat.

via 720 ABC Perth