Cartoon guide to biodiversity loss XLI

26 04 2017

Number 41 of my semi-regular instalment of biodiversity cartoons, and the first for 2017. See full stock of previous ‘Cartoon guide to biodiversity loss’ compendia here.

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Cartoon guide to biodiversity loss XL

7 12 2016

That’s ’40’, of course. Six more biodiversity cartoons, and the last for 2016. See full stock of previous ‘Cartoon guide to biodiversity loss’ compendia here.

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Cartoon guide to biodiversity loss XX

20 08 2013

I can’t believe I’ve now done twenty of these – another 6 biodiversity cartoons while I’m travelling (see full stock of previous ‘Cartoon guide to biodiversity loss’ compendia here).

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Cartoon guide to biodiversity loss XIX

3 06 2013

Here are 6 more biodiversity cartoons illustrating through humour the sad state of the natural world (see full stock of previous ‘Cartoon guide to biodiversity loss’ compendia here).

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The Biodiversity Club

11 10 2012

The International Union for Conservation of Nature (IUCN) Red List of Threatened Species uses 5 quantitative criteria to allocate species to 9 categories of extinction risk. The criteria are based on ecological theory (1, 2), and are therefore subject to modification and critique. With pros and cons (3-6), and intrigues (7, 8), the list has established itself as an important tool for assessing the state of biodiversity globally and, more recently, regionally.

We all carry codes of some sort; that is, unique alphanumeric labels identifying our membership in a collectivity. Some of those codes (e.g., a videoclub customer number) make sense only locally, some do internationally (e.g., passport number). Species are also members of the club of biodiversity and, by virtue of our modern concern for their conservation, the status of many taxa has been allocated to alphanumeric categories under different rationales such as extinction risk or trading schemes (5, 9-13). Contradiction emerges when taxa might be threatened locally but not internationally, or vice versa.

In the journal Biological Conservation, a recent paper (14) has echoed the problem for the seagrass Zostera muelleri. This marine phanerogam occurs in Australia, New Zealand and Papua New Guinea, and is listed as “Least Concern” (LC) with “Stable” population trend by the IUCN. Matheson et al. (14) stated that such status neglects the “substantial loss” of seagrass habitats in New Zealand, and that the attribution of “prolific seed production” to the species reflects the IUCN assessment bias towards Australian populations. The IUCN Seagrass Red List Authority, Fred Short, responded (15) that IUCN species ratings indicate global status (i.e., not representative for individual countries) and that, based on available quantitative data and expert opinion, the declines of Z. muelleri are localised and offset by stable or expanding populations throughout its range. Read the rest of this entry »

Restoring doomed fish

24 08 2012

I get called a doomsday merchant a lot, mainly because there’s not a lot of good news out there when it comes to biodiversity these days. However, now and again there is a success story worth shouting from the rooftops. This latest post comes from my PhD student, Jarod Lyon (also of the Arthur Rylah Institute in Victoria), who is working on restoring native freshwater fish in Australia’s largest river system – the Murray-Darling. The M-D also happens to be in a lot of trouble because of poor water management and years of neglect. However, some clever research and restoration proves that we can bring biodiversity back from the brink if done right. Jarod has posted here on Conservation Bytes before describing his work, and this latest post provides some detail on one species in particular.

Trout cod Maccullochella macquariensis were once considered to be widespread in the southern tributaries of the Murray-Darling Basin. However over the past fifty years, their distribution and abundance have declined dramatically, due to a number of disturbances including habitat loss, altered flow and temperature patterns, in-stream sedimentation, population fragmentation due to in-stream barriers and over fishing. Trout cod are listed nationally as endangered under the Environment Protection and Biodiversity Conservation Act (EPBC Act 1999) and listed under the Victorian Flora and Fauna Guarantee Act (FFG Act 1988). Trout cod are often accidentally caught when fishing for Murray cod. However, it is illegal to take a trout cod while angling.

Trout cod were historically abundant in the lower Ovens River system in South-Eastern Australia, however were locally extinct by the 1980s. In an attempt to re-introduce a viable population in the Ovens River, hatchery-reared juvenile trout cod were stocked in the Ovens River system for ten years starting in 1997. Our recent manuscript published in Marine and Freshwater Research assesses the success of this stocking regime (particularly in relation to recovery plan objectives) through a variety of techniques, including fish surveys and analysis of gonads, otoliths and genetic structure of the population.

We found that the Ovens River now holds a naturally self-sustaining population of trout cod – that is, the progeny of stocked fishes are now breeding.  Given that most threatened species re-introduction programs worldwide fail, this is somewhat of a good-news story for management of rare animals. In particular, we found that the length of the stocking program was a major factor in its success, as the long time period overcame the years where the survival of the stocked fingerlings was low. Interestingly, most fish to recruit to an adult size were stocked in 2003 or 2004 – meaning if this had been a five-year program, it would most likely have failed. Read the rest of this entry »

Simple educational tool to explain biodiversity

26 08 2010

I just came across this little educational video explaining what biodiversity is, what it does, and what we’re doing to it. If you’re looking to explain biodiversity and its importance to someone, this is a good place to start. Not a bad tool for school children either.

CJA Bradshaw