To develop or not to develop? That is the question framing biodiversity conservation

Isobel Bender u6673141 – 550 words

It is an unfortunate conundrum, that while biodiversity (diversity within species, between species and of ecosystems) is declining at a rate faster than any other time in human history, sites of high conservation value can also be ideal areas for urban and agricultural development. In turn, habitat modification continues to be a major driver in biodiversity decline.

This is the conundrum facing the Delma impar or the Striped Legless Lizard (SLL). The SLL is dependent on the critically endangered vegetation community of the Natural Temperature Grassland, 99% of which has been lost or altered since European settlement due its suitability as agricultural land. In August, I volunteered to help the ACT Parks and Conservation Service (PCS) in a conservation strategy that aims to address this conundrum and protect the SLL – the strategy of biodiversity offsets.

*Delmar impar or the Striped Legless Lizard. Photo*: *Emily Sutcliffe 14th of October 2022*

Biodiversity offsets – have your cake and eat it too?

Biodiversity offsets in Australia are designed to compensate for adverse impacts to protected matters like the SLL, which is listed as vulnerable under the Commonwealth Environmental Protection and Biodiversity Conservation Act 1999 (EPBC Act). In the ACT, several urban development sites negatively impacted the SLL and the developers were required to protect several areas with known populations of SLL (offset sites). PCS are required to manage these areas to ensure there is no further loss of habitat for the SLL.

In turn, the establishment of the offset sites are trying to marry the two contradictory pursuits – the need for development and the need for conservation – to ensure ‘no net loss’ of the SLL.

Tiles – home away from home

Part of the offset management strategy is to monitor the populations of SLL. This is where I came in. Over a couple of days, I worked out my muscles by carrying around 3kg roof tiles to set up monitoring plots. Within a monitoring plot, we placed 8 tiles in a square, with the tiles facing North and the darker side facing up to ensure heat conduction. The tiles are to create an artificial habitat to attract the SLL. Then in September through to December, the tiles are checked to record:

the percentage of tiles occupied by SLL and
the average number of SLL per plot.

This data is used to help detect any drivers of change in the population of SLL, anticipate any future changes and to inform management actions.

*Example diagram of the tile setup to monitor the Striped Legless Lizard. Diagram adapted by author*.

Closed loop or monitoring to death?

Biodiversity offsets is a controversial conservation strategy, where it is perhaps counterintuitive – there can be ‘no net loss’ in biodiversity while development detrimental to its continuance is approved. Yet this critique aside, while volunteering I found out the SLL population has continued to decline across the offset sites despite protection, management, and monitoring. This is also despite ACT Parks and Conservation identifying the driver of this population decline for two consecutive years as too intense grazing pressure within the offset sites.

This makes apparent that a conservation strategy alone is not enough to conserve biodiversity, and largely relies on an effective monitoring strategy.

Effective monitoring is meant to be like a closed loop – where monitoring data like population decline is linked to a particular driver of change and in turn, informs the effectiveness of a management action. This may trigger a change in management action, the results of which are monitored, and the loop continues. Unfortunately, monitoring strategies are rarely implemented in a way to ensure conservation success. Hopefully, PCS will make efforts to close this loop and adjust current management strategies to halt further decline of the SLL.

*Example of an adaptive monitoring strategy for the Striped Legless Lizard. Diagram: author.*

*Striped Legless Lizard found under monitoring tile during 2022 surveys. Photo: Emily Sutcliffe 14th of October 2022*

Note: The locations of the offset sites for SLL have not been referenced in this blog. The SLL is a threatened species and ACT Parks and Conservation service do not want to broadcast where the SLL are to minimise the risk of people checking the tiles by themselves and disturbing the areas. The monitoring method used is carefully thought out to minimise risks to SLL and other reptiles and has the required animal research ethics approval.

References

Convention of Biological Diversity 1992 (CBD)

Department of Climate Change, Energy, the Environment and Water (DCCEEW) 2022. ‘Delma impar — Striped Legless Lizard, Striped Snake-lizard.’ Available at: http://www.environment.gov.au/cgi-bin/sprat/public/publicspecies.pl?taxon_id=1649 (Accessed 25.09.2022).

Dixon, K.; Cary, G.; Worboys, G.; Banks, S.; Gibbons, P. 2019. Features associated with effective biodiversity monitoring and evaluation. Biological Conservation. Vol. 238. pp: 108221

Environment, Planning and Sustainable Development Directorate (EPSDD) 2015. ‘Striped Legless Lizard Delma Impar: Action Plan.’ Environment, Planning and Sustainable Development Directorate, Canberra.

Environment, Planning and Sustainable Development Directorate (EPSDD) 2020. ‘Environmental Offsets Ecological Monitoring Program Report 2018–19.’ Environment, Planning and Sustainable Development Directorate, Canberra.

Environment, Planning and Sustainable Development Directorate (EPSDD) 2021. ‘Environmental Offsets Ecological Monitoring Program Report 2019–20.’ Environment, Planning and Sustainable Development Directorate, Canberra.

Environment, Planning and Sustainable Development Directorate (EPSDD) 2022. ‘Offsets register.’ Available at: https://www.planning.act.gov.au/tools-resources/plans-registers/registers/offsets-register (Accessed 25.09.2022).

Gibbons, P.; Lindenmayer, D. 2012. ‘Biodiversity monitoring in Australia.’ CSIRO Publishing. Collingwood, Victoria.

Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) 2019. ‘Summary for policymakers of the global assessment report on biodiversity and ecosystem services of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services.’ IPBES secretariat. Bonn, Germany.

Maron, M.; Ives, C.; Kujala, H. 2016. Taming a wicked problem: resolving controversies in Biodiversity Offsetting. BioScience. Vol. 66. pp: 489-498.

Miller, K.; Trezise, J.; Kraus, S.; et al 2015. The development of the Australian environmental offsets policy: from theory to practice. Environmental Conservation. Vol. 42. No.4. pp: 306-314.