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#ProjectedAreas are the main tool on which our hopes rest for halting & reversing biodiversity declines! But do they work? Not a simple question -> We review the multifaceted challenges of evaluating PA effectiveness in a new article @NatureComms 1/12 https://www.nature.com/articles/s41467-020-18989-2
#ProtectedAreas are *means* for achieving conservation *ends*! Means translate into ends if PAs are effective at abating threats & enhancing long-term resilience. Evaluations of PA effectiveness can focus on the *means*, on the *ends*, or on the *mechanisms* linking the two 2/12
Most analyses of #ProtectedArea effectiveness focus on the *means* of protection: extent of the network, management inputs, location.
Measuring extent is possible thanks to the World Database on Protected Areas 3/12
@unepwcmc @IWcpa https://livereport.protectedplanet.net/
Measuring extent is possible thanks to the World Database on Protected Areas 3/12
@unepwcmc @IWcpa https://livereport.protectedplanet.net/
#ProtectedAreas can only work if adequately managed! Many aren't. Evaluating management effectiveness typically involves questionnaires to PA managers re. management inputs (staff, resources), processes, outcomes 4/12 https://pame.protectedplanet.net/
#ProtectedAreas can only be expected to protect the biodiversity they cover in the first place. Evaluating their ecological representativeness involves crossing PA location with biodiversity layers, such as species ranges from the @IUCNRedList (ex: https://www.nature.com/articles/s41586-020-2773-z) 5/12
Overall, we need #ProtectedAreas that are individually effective (well-designed, well-managed, strategically located) as well as well-connected, in sufficient extent & representative of biodiversity to add to an efficient global PA network -> the *means* for effectiveness 6/12
If *means* are adequate, the effectiveness of #ProtectedAreas should then become apparent by their effect at abating threats to biodiversity and at increasing the resilience of ecosystems to global change (locally & globally) -> the *mechanisms* for PA effectiveness 7/12
Most evaluations of *mechanisms* of #ProtectedArea effectiveness focus on effects at reducing habitat loss (eg avoided deforestation https://www.pnas.org/content/116/46/23209 
) using satellite imagery. Effects on other threats (eg overexploitation, invasives) much more difficult to assess 8/12
) using satellite imagery. Effects on other threats (eg overexploitation, invasives) much more difficult to assess 8/12
Ultimately, #ProtectedAreas only work if they are achieving conservation outcomes: locally in individual PAs; collectively by adding to global effects. Evaluating these *ends* is not easy; hence, few studies. 9/12
Assessing if #ProtectedAreas make a difference to species means comparing protected sites with a #counterfactual = what would have happened in the same sites without protection? This requires fine-scale field data, both inside & outside PAs (eg. https://www.nature.com/articles/s41467-020-18230-0) 10/12
Previous analyses of #ProtectedArea effectiveness in terms of *ends* (=biodiversity outcomes) measure average local effects of individual sites. Holy Grail of assessing PA effectiveness: quantify the contribution of the overall PA network to global conservation outcomes. 11/12
This paper was done in collaboration with Victor Cazalis.
12/12
@umontpellier @cefemontpellier @INEE_CNRS https://www.nature.com/articles/s41467-020-18989-2
12/12
@umontpellier @cefemontpellier @INEE_CNRS https://www.nature.com/articles/s41467-020-18989-2
I unwittingly created the hashtag #ProjectedAreas in the first tweet of this thread... 
Which neatly summarises the key message of the thread: #ProjectedAreas are not enough; we need #ProtectedAreas!
Which neatly summarises the key message of the thread: #ProjectedAreas are not enough; we need #ProtectedAreas!
