Wednesday, December 1, 2021

December 2021 Science Summary

Yellowjacket on bird bath

Happy December,

This month I have three articles all about how we can do better at conservation!

The first one (Guadagno et al. 2021) is about how we can get better at learning from failure and improving on success (as individuals, teams, and organizations) - make time to read this one (or at least skim the sections that look most relevant to you). It's worth it. The next one (LeFlore et al. 2021) looked at what aspects of research led to it being used to inform decision-making. And Pressey et al. 2021 argues that by focusing on area of protection (rather than avoided habitat and species loss), conservation is having less impact than we hope for.

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Guadagno et al. 2021 is an an excellent new report from the Wildlife Conservation Society (as part of the Failure Factors Initiative) looking at the experience of conservation NGOs with using “pause and reflect” sessions to learn from failure (and success). Here are my key take-aways:

  • People are reticent to talk publicly about failure for fear of losing respect, status and support for their work.
  • Documenting “lessons learned” in reports is not as important as staff going through the process of talking together and informally learning from each other.
  • Regularly reflecting on both what is working well and what could be improved (even for minor things, and for both successes and failures) makes teams better equipped to respond to serious or major failures (see Example 4 on p14). Having already built both trust and familiarity with a healthy way to learn from failure is excellent preparation when crises arise, allowing the group to work together to pivot effectively. These sessions don't have to take much time.
  • Those regular reflections work best when there is high psychological safety (be respectful, focus on what happened and what to do next time and not who is to blame, recognize and address bias) and they are structured around a few core questions (what did we expect to happen vs. what happened, what went well and why, what can be improved and how). See page 21-25 for recommendations on how to do this, as well as guides / questions you can use.
  • Sometimes a failure looks like a success at first, and in these reflections you can look for other explanations for apparent success (as per Example 1 on p7) allowing you to identify hidden problems and resolve them.
  • Other times, a failure is at least partially a success, and these sessions can also identify some aspects of work going well even when we don’t achieve the outcomes we hoped for (see Example 2 on p11). Also even successes can probably be improved! (see Example 3 on p13).

LeFlore et al. 2021 looks at factors that tend to result in research being used via a focus on 40 small-scale conservation research projects on the Salish Sea. They found having a government collaborator was key, as was stakeholder engagement throughout the process, and that publishing a journal article didn't increase the chances of the research being used to inform decision-making. The impact bit was self-reported so I was pretty surprised only 40% of the projects were reported as leading to impact! It's hard to know how generalizable their results are, but I think it's fair to ask researchers to compare the time it takes to substantially engage w/ decision makers and other stakeholders, compare that to the time needed to publish, and to reflect on which is a higher priority use of their time. Full disclosure: I was a peer-reviewer of this paper.

Pressey et al. 2021 is an opinion piece arguing that conservationists need to shift focus from area-based protection targets (even those including representation) to avoided biodiversity loss (species extinction and habitat destruction) and ecological recovery. They make a fair and important point: despite increasing protection, the overall global trend of species and habitat loss isn't declining. So protected areas aren't working effectively (whether they're not managed well, or in the wrong places, or there still aren't enough of them, or a mix). That's hard to argue with, and it's key that we find a way to better mitigate acute threats. But they lose me when they call for a lot more modeling of counterfactuals and monitoring of outcomes relative to the modeling. I've done that modeling, and it's slow, expensive, and subject to lots of assumptions and uncertainty. So rather than shifting lots of implementation dollars to more science, I'd favor using 'just enough' science to identify key needs for conservation, push advocacy to focus more on those needs than is currently happening, and do more spot monitoring to check efficacy and adapt.

Guadagno, L., Vecchiarelli, B. M., Kretser, H., & Wilkie, D. (2021). Reflection and Learning from Failure in Conservation Organizations: A Report for the Failure Factors Initiative.

LeFlore, M., Bunn, D., Sebastian, P., & Gaydos, J. K. (2021). Improving the probability that small‐scale science will benefit conservation. Conservation Science and Practice, October.

Pressey, R. L., Visconti, P., McKinnon, M. C., Gurney, G. G., Barnes, M. D., Glew, L., & Maron, M. (2021). The mismeasure of conservation. Trends in Ecology & Evolution, 36(9), 808–821.

p.s. Anyone know what species of ground yellowjacket this is? It was drinking from the rim of my birdbath!

Monday, November 1, 2021

November 2021 science summary

Meteor by Robert Roselle


This month I am summarizing a mixed bag of science articles on conservation planning, climate change, fire & human health, and wildlife monitoring.

I was interviewed by Wildhub about things I've learned as a conservation scientist (especially related to publishing papers), if you're interested it's available at:

Also the 2021 Annual Request for Proposals (RFP) from The Science for Nature and People Partnership (SNAPP) is now open. You can learn more and apply at (proposals due by December 10th), but they fund quick working groups to advance research w/ tangible benefits to people and nature.

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Lees et al. 2021 is an interesting analysis of the impact of participatory and stakeholder-inclusive conservation planning on threatened species. They specifically look at the 35 planning workshops hosted by The Conservation Planning Specialist Group (CPSG) of the IUCN Species Survival Commission (IUCN SSC) which had data for at least 5 years before the workshop and 10 years after on the species in question (using the Red List Index). The abstract tells a rosier picture than does Table 1: 10 years after workshops 4% of spp improved, 22% declined, and 74% were stable (after 15 years it was 9%, 26%, and 66%). But 1) they show that the decline slowed down post-workshop relative to pre-workshop, and 2) relative to a modeled counterfactual (w/o the workshops) they predicted that 8 species extinctions were avoided (of the 35 spp. with 15 years of post-workshop data). Check out Fig 3 for the mean risk over time which makes their point well. While it's posisble the 15 year data is an anomaly, in the discussion on p6 they make a good case that the workshops were the secret sauce rather than some other factor. Since they take place in contexts where past conservation has been unsuccessful and the path forward was unclear due to conflicting views and uncertainty, the pre-workshop outlook was typically poor, and actively including stakeholders in planning was a good way to both find solutions and build support for them. Studying the impact of planning per se is very difficult, and I don't see this paper as definitive proof, but it is useful evidence making a case for broad and inclusive planning that involves a range of stakeholders.

Dobrowski et al. analyzes how much of the world will experience enough climate change to effectively shift into a different ecoregion, and how that relates to protected areas (PAs). They move ecoregions' location to keep their historic climate similar, which is an interesting thought exercise but not a likely scenario (given variations in soil and topography and other factors that will not shift w/ climate). They found that with 2C warming, 54% of land will effectively change ecoregions, with 22% shifting biomes (see Fig 4 for how this affects % protected by biome). This means there are winners and losers, with the biggest losers the ~5% of land within PAs that don't have an analogous climate w/in 2000 km for species to migrate to (shown in black in Figs 2b & 3b; 56 ecoregions 'disappear'). They recommend a focus on unmodified areas expected to be climatically stable that are currently underprotected, as well as areas that improve climate connectivity (see Fig 6 for a case study in the NW US and Canada). They also have a tool where you choose a place, and it'll tell you what other place currently has the climate the first place is expected to have w 2C (or 4C) warming:

Liu et al. 2017 combines modeled smoke exposure from wildfire with hospital admission data (due to respiratory illness) to estimate the health impacts of fire on different groups of elderly Medicare enrolees. Specifically, they looked at age, gender, race, urban/rural, region, poverty level, and education (see Table 2) in 561 counties in the Western US. They looked at baseline hospital admissions for respiratory illness for each group, and then how that changes on days when smoke levels are high. They found more smoke exposure in Blacks, California, urban, and more educated counties. Hospital admissions on smoke days increased the most for Blacks (22%) and women (10%). There are a few odd findings (like poor people having more smoke exposure, but decreased hospital admissions on smoke days), and they also used a bad practice of having a 'referent' population that was white, make, urban, and relatively wealthy and young.

Palaiologou et al. 2019 looked at how different aspects of the Social Vulnerability Index affect wildfire exposure in parts of three states (WA, CA, NM). They grouped social attributes oddly rather than using the default SVI themes (see Table 2: I'm unclear why 'minority' ends up in 'education'), but found fire exposure went up w/ poverty & disability, higher population & # of households, youth, inability to speak English, and lack of high school education (but with variation by state). They found that most fire exposure for the most vulnerable places originated on private land relatively near to both towns and "wildlands."

Lahoz-Monfort & Magrath 2021 is an overview of tech options for monitoring wildlife (excluding biotechnology like eDNA and genomics) and to a lesser degree collecting other environmental information. Since they cover a wide range of tech fairly shallowly, it's hard to summarize. It's worth a quick read for anyone looking to understand the range of ways scientists track and measure wildlife from afar. They cover types of sensors (chemical, thermal, optical including UV and IR but broken out from multispectral and hyperspectral and LiDAR, radar, active sonar, passive acoustic, vibration, and position / motion), specific devices (visible and thermal camera traps, microphones w/ loggers, sonar on boats or buoys, land-based radar like Doppler, smartphones, and a few others), networks of devices (wireless or independent but with data harvested and combined later), devices on land and water vehicles, traditional remote sensing (from planes, satellites, and drones), devices on animals (which can track: location via several tech options, physiological info like temperature and heart rate or even birth, imagery, audio, individual identity, interactions w/ other animals, and more), other ways to track the location of wildlife, using sensors to trigger traps (or deploy poison or open / close a gate, etc.), and computing (including online platforms, smartphones, AI, and cheap computing).

Dobrowski, S. Z., Littlefield, C. E., Lyons, D. S., Hollenberg, C., Carroll, C., Parks, S. A., Abatzoglou, J. T., Hegewisch, K., & Gage, J. (2021). Protected-area targets could be undermined by climate change-driven shifts in ecoregions and biomes. Communications Earth & Environment, 2(1), 198.

Lahoz-Monfort, J. J., & Magrath, M. J. L. (2021). A Comprehensive Overview of Technologies for Species and Habitat Monitoring and Conservation. BioScience, 71(10), 1038–1062.

Lees, C. M., Rutschmann, A., Santure, A. W., & Beggs, J. R. (2021). Science-based, stakeholder-inclusive and participatory conservation planning helps reverse the decline of threatened species. Biological Conservation, 260(December 2020), 109194.

Liu, J. C., Wilson, A., Mickley, L. J., Ebisu, K., Sulprizio, M. P., Wang, Y., Peng, R. D., Yue, X., Dominici, F., & Bell, M. L. (2017). Who Among the Elderly Is Most Vulnerable to Exposure to and Health Risks of Fine Particulate Matter From Wildfire Smoke? American Journal of Epidemiology, 186(6), 730–735.

Palaiologou, P., Ager, A. A., Nielsen-Pincus, M., Evers, C. R., & Day, M. A. (2019). Social vulnerability to large wildfires in the western USA. Landscape and Urban Planning, 189(April), 99–116.

p.s. the photo above shows the inside of a sculpture called Meteor by Robert Rosselle (the last one he made before he died). The outside is less lovely ( so it's a great surprise to peek in and see the planet and stars

Monday, October 11, 2021

Wildhub interview on publishing and science communications

Spatial Data Publishing Workshop

I was recently interviewed for Wildhub (a member-led website where conservation professionals from around the world can post) about scientific publishing and communications. 

We talked about how publishing can be important, why we wrote the paper on how scientists can improve their impact, challenges in writing that paper, finding co-authors, dealing with criticism and rejection, and the importance of persisting in sharing your message.

Friday, October 1, 2021

October 2021 science summary

Jon digging a hole with an excavator / backhoe



Before diving into journal articles, I want to highlight a blog, short video, and web map update. First, over the last several years of working in conservation, I hear more and more calls for conservation to rapidly scale effective solutions. Sometimes that's coupled with a sense of urgency that makes us think we don't have time for missteps or to do things that don't work. But this article makes a compelling case that if we want to scale fast, that means we will need a higher tolerance for the risk of failure. It's a good read!

Want to know how (and why) to talk to "uncle Ernie" and other people who are not convinced we need to urgently act on climate change? Check out Dr. Katherine Hayhoe's interview on Jimmy Kimmel:

The last quick update is for those of you working in South America. The latest update to Mapbiomas includes fire scars and water surface area: 
They have cool graphs showing changes (drops) in water area over time. The (user's) accuracy is mostly 75% or above, but it's really low in the Pantanal (see They saw a huge drop there (74% less water over 30 years) but it's hard to know how much of that is real. Unfortunately the high variation throughout the year makes validating annual estimates of water surface inherently tricky.

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Welsby et al. 2021 ask an interesting question: what fraction of economically viable fossil fuels need to left in the ground to give us a 50% shot at limiting warming to 1.5C? The answer is pretty stark: by 2050 we need to leave 58% of oil, 59% of methane gas, and 89% of coal underground (a 3% annual reduction in oil and gas). See table 1 for their estimates by region. They note that we may need to leave even more fuels unextracted given questions about how fast we can develop "negative emissions" technology (carbon capture and storage).

Zhang et al. 2020 finds that 3.7% of total natural gas (mostly methane) extracted in the Permian basin (west Texas and SE New Mexico) is lost via leaks (w/ 4.1% lost in the Delaware sub-basin). It's a cool study using a recent satellite to estimate methane emissions, and EDF is launching a more precise satellite for this in 2022. This is a big deal because given methane has ~84 times the impact of CO2 on global warming over the next 20 years (dropping after that). So this leakage rate means that right now natural gas from the Permian has more short-term climate impact than coal (see! The authors think the leaks in this region are mostly from venting and flaring during active production (as opposed to leaks after well abandonment)

Sala et al. 2021 identify global priorities to designate as marine protected areas (MPAs), with the goal of protecting biodiversity and carbon while improving the yield of fisheries. The yield improvements come from targeting areas that are currently both overexploited and unprotected; they find protecting 9% of the ocean could boost maximum sustainable yield (MSY) from seafood by about 10% (protecting 5% increases yield by ~9%, Fig 1d,). The authors recommend protecting 28% of the ocean (not 9%) but their data seem to indicate the food benefit is the same at both levels. Fig 3 has some other interesting scenarios, including giving equal weight to food and biodiversity (3c, leading to a recommendation to protect 45% of the ocean which provides 92% of maximum fisheries benefit, 71% of max. biodiversity benefit, and 29% of max carbon benefits) or maximizing biodiversity without harming production (3d, recommending to protect 71% of the ocean which provides neither fisheries benefit nor harm, 91% of max. biodiversity benefit, and 48% of max carbon benefits). The unequal distribution of priority areas (Fig 1 & 2) raise potential equity concerns that are not addressed. Also apparently the carbon estimates do not account for additional boat travel time and thus may be optimistic. Finally: I know very little about marine ecosystems so let me know if you think my summary is wrong.


Sala, E., Mayorga, J., Bradley, D., Cabral, R. B., Atwood, T. B., Auber, A., Cheung, W., Costello, C., Ferretti, F., Friedlander, A. M., Gaines, S. D., Garilao, C., Goodell, W., Halpern, B. S., Hinson, A., Kaschner, K., Kesner-Reyes, K., Leprieur, F., McGowan, J., … Lubchenco, J. (2021). Protecting the global ocean for biodiversity, food and climate. Nature, 592(7856), E25–E25.

Welsby, D., Price, J., Pye, S., & Ekins, P. (2021). Unextractable fossil fuels in a 1.5 °C world. Nature, 597(7875), 230–234.


p.s. the photo above is of me driving an excavator at Diggerland, which was quite fun albeit not the greenest activity

Wednesday, September 1, 2021

September 2021 science summary

Climate emission curves


This month is all about climate change (the photo above is from mini golf course in Brooklyn, where the three paths represent emissions scenarios).

First - I want to clarify something from last month's update. I mentioned that big old trees are especially important for carbon sequestration, and that increasing the length of time between forests being logged and/or leaving the biggest trees can be helpful to retain that carbon. But the term "proforestation" that I used is apparently commonly used to mean no forest management at all. That means eliminating any tree cutting at all (not just commercially, but even for pest management, fire control, or ecological goals). While logging can have environmental downsides (including for carbon), wood products are also relatively sustainable, and cutting trees is one of several important forest management tools that may be useful even in lands managed primarily for conservation. In cases where not cutting trees increases the risk of severe fire, that could even lead to worse outcomes for carbon sequestration and storage. Apologies for the poor choice of language.

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You probably have heard that the 2021 IPCC report came out this month: Don't feel like reading 1800 pages or even the 90 page summary or 215 page FAQ? Check out the 2 page 'headline statements' here:
The one thing to highlight for me is that limiting warming to 1.5C is now harder but not impossible (requiring net zero by 2055 w/ 90% gross emissions reductions). Current policies agreed to under Paris would still lead to 3C warming by 2100. One finding that I read about in this New York Times article ( really struck me: a bad heat wave that used to happen every ~50 years is now happening every ~10 years, and will happen every ~5 years at 1.5C or nearly annually at 4C. Don't miss this interactive tool to explore the results (and note you can download spatial data via the "share" icon):

Want some good news about climate? Costa et al. 2021 have a brief overview of the use of GWP* as a way to calculate the global warming potential of methane (CH4) more accurately than GWP100 (100 year warming). This is super-tricky and took me a while to wrap my head around, but the basic issue is that because methane is naturally breaking down over time, GWP* looks at emissions 20 years ago (which are now breaking down into CO2) to understand net changes in CH4 (as opposed to GWP100 which treats it as constant over 100 years). It means that relatively small reductions in biogenic methane (mostly from livestock and soil) emissions could get us to a stable point where globally methane is emitted and broken down at the same rate. Since the CO2 that feeds into biogenic CH4 is pulled out of the atmosphere via feed, that means it's arguably easier than we thought earlier to get to the point where globally biogenic methane isn't causing warming. Two big caveats: 1) this doesn't apply to fossil methane (where the end product of CO2 is pulled out of the ground, leading to a net increase), 2) this only makes sense when estimating global methane levels, and NOT in thinking about reductions at a local level. The latter point is important - a company or country could use this metric to make small reductions in livestock emissions and "take credit" for the breakdown of high past levels, and argue they are carbon negative (they are not). But if you take away the attribution issue, and focus on estimating warming, this offers an improvement. Let me know if this is still confusing to you, and/or you think I got this wrong!

Green et al. 2019 quantify the well known issue of climate and soil moisture having a big impact on carbon sequestration. Using climate projections (now out of date w/ the 2021 IPCC report) they find that as climate gets more variable, carbon sequestration and storage by plants will strongly decline (offsetting CO2 fertilization by 2060 under conservative assumptions). By 2085 carbon sequestration will have fallen to half of what it would have been without the moisture variability. The potential  carbon lost through drought and fire exceeds potential carbon gains from unusually wet conditions. This is mostly b/c plants get a lot less productive under drought, while too much water doesn't spur lots of growth (and can even be harmful with floods). Surprisingly they focused on plant biomass rather than modeling soil carbon changes, nor did they look at the impact of this changing soil moisture on methane or nitrous oxide soil emissions. There's a summary of this paper at

Fox et al. 2018 looked at how common parasites in lambs impact methane production. I was intrigued by the title (which says they drive a 33% increase in 'methane yield') which seemed to indicate a huge potential to reduce GHGs from lamb through medical treatment. But that is a fairly artificial metric of methane emissions per mass of feed. A more meaningful metric is total methane emissions (fig 2), which were highest in healthy lambs eating a normal diet, moderately lower in parasitized lambs, and slightly lower than that in healthy lambs eating less to control for the weight loss impact of parasites. Usually the main metric is emissions per kg of meat; I estimated this from final body weight using table 1 and figure 2 and it looks like healthy lambs emitted ~1.83 daily g CH4 / kg final body weight, parasitized lambs emitted ~1.67 daily g CH4 / kg final body weight, and healthy lambs on a restricted diet emitted ~1.62 daily g CH4 / kg final body weight. My take away from this paper is that eliminating parasites is unlikely to deliver much climate mitigation (in this case without dietary adjustment would INCREASE GHGs), although it may be desirable from an animal welfare or efficiency perspective.


Costa Jr, C., Wironen, M., Racette, K., & Wollenberg, E. (2021). Global Warming Potential* (GWP*): Understanding the implications for mitigating methane emissions in agriculture. CCAFS Info Note. Wageningen, The Netherlands

Fox, N. J., Smith, L. A., Houdijk, J. G. M., Athanasiadou, S., & Hutchings, M. R. (2018). Ubiquitous parasites drive a 33% increase in methane yield from livestock. International Journal for Parasitology, 48(13), 1017–1021.

Green, J. K., Seneviratne, S. I., Berg, A. M., Findell, K. L., Hagemann, S., Lawrence, D. M., & Gentine, P. (2019). Large influence of soil moisture on long-term terrestrial carbon uptake. Nature, 565(7740), 476–479.

IPCC, 2021: Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change [Masson-Delmotte, V., P. Zhai, A. Pirani, S. L. Connors, C. Péan, S. Berger, N. Caud, Y. Chen, L. Goldfarb, M. I. Gomis, M. Huang, K. Leitzell, E. Lonnoy, J. B. R. Matthews, T. K. Maycock, T. Waterfield, O. Yelekçi, R. Yu and B. Zhou (eds.)]. Cambridge University Press. In Press.

p.s. Here's one more picture from the climate change mini golf course, showing a polar bear on melting ice floes 

Monday, August 2, 2021

August 2021 science summary


This month is a grab bag of a few articles on different topics I've been meaning to read. Sorry for the lack of a theme!

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Maron et al. 2021 offers seven guidelines to set robust biodiversity goals (aimed at the Global Biodiversity Framework [GBF] under CBD), summarized in a nice diagram in Fig 1. 1. recognize limits to "net outcome" approaches (determine which spp and ecosystems are irreplaceable), 2. use net outcomes where needed since some losses are unavoidable, 3. specify a timeline for net outcome goals (a reference year and a target year), 4. set goals for net gains (since a reference year like 2020 has some spp. and ecosystems which have experienced high historic loss, so net gaines are needed to persist), 5. capture key biodiversity (with distinct goals for ecosystems, spp., and genetic diversity), 6. avoid unintended substitutions by ensuring any losses to one species (or ecosystem) is balanced with gains to a different one only if the losses are to a relatively unthreatened component, and 7. set ambitious goals (achievable, but more than adequate). They note several changed needed to the post-2020 GBF to meet these criteria.

Lutz et al. 2018 asks how important the biggest trees in forests are across the world. My favorite figure is that the biggest 1% in diameter made up ~50% of the aboveground biomass (of trees bigger than 1 cm), although with lots of variation by forest. If you use a consistent threshold of trees >2' in diameter instead of the top 1%, they're ~40% of biomass on average. Forests where the biggest trees took up a bigger % of total biomass tended to have fewer species in that top size class. They point out that for carbon sequestration, these big trees are super important, which Bill Moomaw has also emphasized in advocating for 'proforestation' where we just leave forests alone for longer before logging them as the rate of sequestration goes up as they get really big.

Hall et al. 2021 is about Circuitscape (software to analyze wildlife connectivity at the landscape scale) and the advantages of having ported it over to Julie (a high-performance computing language). From figure 3 it looks like the new version is about 7 times as fast as the python version, and it runs as a standalone without needing to know Julia. They make the broader point that collaborating with computer scientists can reduce costs and improve efficiency, allowing more conservation to get done.

Dieckman et al. 2021 surveyed people about how important different social and cultural issues were to government decision makers vs. the general public. Respondents thought that government decision makers care the most about economic aspects, but that the public cares more about other social and cultural aspects. More tangible impacts (like water quality and physical safety) were perceived to be more important than intangible ones (like emotional health and local practices). Interestingly, biodiversity had the lowest perceived support second only to native culture.


Dieckmann, N. F., Gregory, R., Satterfield, T., Mayorga, M., & Slovic, P. (2021). Characterizing public perceptions of social and cultural impacts in policy decisions. Proceedings of the National Academy of Sciences, 118(24), e2020491118.

Hall, K. R., Anantharaman, R., Landau, V. A., Clark, M., Dickson, B. G., Jones, A., Platt, J., Edelman, A., & Shah, V. B. (2021). Circuitscape in Julia: Empowering Dynamic Approaches to Connectivity Assessment. Land, 10(3), 301.

Lutz, J. A., Furniss, T. J., Johnson, D. J., Davies, S. J., Allen, D., Alonso, A., Anderson-Teixeira, K. J., Andrade, A., Baltzer, J., Becker, K. M. L., Blomdahl, E. M., Bourg, N. A., Bunyavejchewin, S., Burslem, D. F. R. P., Cansler, C. A., Cao, K., Cao, M., Cárdenas, D., Chang, L.-W., … Zimmerman, J. K. (2018). Global importance of large-diameter trees. Global Ecology and Biogeography, 27(7), 849–864.

Maron, M., Juffe-Bignoli, D., Krueger, L., Kiesecker, J., Kümpel, N. F., ten Kate, K., Milner-Gulland, E. J., Arlidge, W. N. S., Booth, H., Bull, J. W., Starkey, M., Ekstrom, J. M., Strassburg, B., Verburg, P. H., & Watson, J. E. M. (2021). Setting robust biodiversity goals. Conservation Letters, May, 1–8.


Thursday, July 1, 2021

July 2021 science summary

Milkweed beetle


This month I've got a few papers on protected areas and three important papers about the role of forests in climate change. The photo above is just a milkweed beetle from my garden whose eye is bisected by its antenna!

Since there's been a lot of interest lately in protected areas and 30x30, I pulled together summaries of some of my favorites here:

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Barnes et al. 2018 highlights the downside of area targets: they may drive siting protected areas (PAs) in bad places and poor enforcement / management. They promote a shift to outcome-based protected area targets (meaning the targets are about biodiversity gains or avoided losses), emphasizing representation and connectivity, and building the evidence base for which factors affect how well PAs deliver conservation outcomes.

Devillers et al. 2015 argues that marine protected areas (MPAs) have largely been cited in remote areas with low threats that the MPAs are intended to address. They point out that politics drive MPAs to be established in places that minimize costs and conflicts with commercial interests, but that MPAs that avoid potential conflicts will by definition have low impact relative to business as usual. They offer two Australian case studies and in particular highlight how well the 2004 rezoning of the great barrier reef was done in terms of improving ecological representation, although still with room to improve. They suggest planners of MPAs and/or no-take zones ask four questions: 1. Are MPAs intended to protect biodiversity? 2. Do proposed MPAs give precedence to more threatened biodiversity features? 3. Do MPAs adequately represent all biodiversity features of interest? and 4. Do MPAs adequately represent variation within features (like bioregions) to focus on the most threatened sub-areas?

Waldron et al. 2020 looks at global financial implications of 30 x 30 (6 terrestrial and 5 marine scenarios), and for tropical forests & mangroves adds in avoided costs and non-monetary ecosystem service values. They estimate that expanding protected areas (PAs) to 30% could result in increased direct global revenues of $64-454 billion / yr (depending on the scenario chosen, and mostly driven by increased nature tourism, see Table 3) as well as more food and wood production. Broader economic benefits (largely from avoided storm damage) could be $170-534 billion / yr more. With a estimated cost of $103-$178 billion / yr (which includes funding to manage existing PAs), they find net economic benefits to 30x30 across all scenarios (spend some time with Table 3 to see the details, but $235 billion / yr is the lowest net financial benefit). It's hard to vet this kind of complex analysis with a ton of assumptions. My gut tells me this is a pretty optimistic assessment due to several key assumptions (like a social cost of carbon at $135-540 / t CO2e , assuming big tourism increases and scarcity of wood driving up forest product revenue, etc.). But they point out that it could be an underestimate since they didn't include broader benefits of other ecosystems like grasslands. Thoughts welcome! Note that other scientists criticized the Waldron paper, noting that not nearly enough has been done to estimate how 30x30 would affect people (nor to consult with them), among other issues. The critique (Agrawal et al. 2020) is here:

Wenzel et al. 2020 (NOAA’s 2020 Marine Protected Area report) has a good overview of marine (and great lakes) protection in the U.S. 26% of US waters are in an MPA, but only 3% in a no-take zone. Page 5 of the PDF has a breakdown by region showing that some places like Alaska are disproportionately unprotected. The report also indicates MPA coverage by habitat type (e.g. 83% of mangroves are protected), calls for OECMs to improve MPA connectivity, and notes the need for better management of MPAs.

As a number of NGOs look to invest in reforestation and forest protection as part of the solution to climate change, Williams et al. 2021 has a very important caveat. They found that while forests cool the earth by sequestering and storing carbon, they can also warm the earth in some cases by absorbing more heat than bare ground or snow would. So some forest loss in the U.S. (lower 48 where they did their modeling) has led to net cooling, even though overall it has led to warming. The cooling mostly happened in the Western US where there’s a lot of snow cover and the arid conditions make for light-color, reflective soils (so losing trees results in less local heat absorption). This paper is more pessimistic than the others I’ve read about temperate forests (for example Li et al. 2015 used remote sensing to actually measure temperature changes and compare nearby pixels with forest vs. open land cover) and finds that 15 years of forest loss only caused warming equal to 17% of a U.S. annual fossil fuel emissions (because the most forest loss has happened in Western states with lots of snow cover, balancing out more moderate forest loss elsewhere). Other work on this topic has found that boreal forests are the most likely to cause net warming (as per Mykleby et al. 2017), but for tropical forest accounting for evapotranspiration and albedo actually enhances their net cooling effect.

Mykleby et al. 2017 estimates how planting trees would affect climate change (both globally and locally) in Canada and the Nothern U.S. They found that in Northern Canada and some Western U.S. states, planting trees would on net warm the earth because the carbon gained is more than outweighed by covering up highly reflective snow with more absorbent tree leaves (Figure 2c). The key point here is that the impact of adding or losing trees depends a lot on location (consistent w/ Williams et al. 2021 and Betts et al. 2000), so tables w/ averages across regions (like Table 1) are not super helpful. This concern with albedo causing local warming is most significant for boreal forests, followed by temperate forests in snowy regions, and does not apply to tropical forests.

Randerson et al. 2006 is another paper looking at how boreal forest loss affects climate change. They used a 1999 boreal forest fire in Alaska as a case study, measuring not only carbon dioxide and methane, but also albedo changes (from exposing snow and ice which reflect more light, and from black carbon deposition which absorb more light) and aerosols in the burned site compared to a control site. They found that for the first ~15 years, the emissions from the fire outweigh the lower albedo and result in net warming. But after 15 years, the fire has a net cooling effect as the GHGs and black carbon and aerosols dissipate, but higher albedo persists (Fig 3b, green line).


Barnes, M. D., Glew, L., Wyborn, C., & Craigie, I. D. (2018). Prevent perverse outcomes from global protected area policy. Nature Ecology & Evolution, 2(5), 759–762.

Devillers, R., Pressey, R. L., Grech, A., Kittinger, J. N., Edgar, G. J., Ward, T., & Watson, R. (2015). Reinventing residual reserves in the sea: are we favouring ease of establishment over need for protection? Aquatic Conservation: Marine and Freshwater Ecosystems, 25(4), 480–504.

Betts, R. A. (2000). Offset of the potential carbon sink from boreal forestation by decreases in surface albedo. Nature, 408(6809), 187–190.

Li, Y., Zhao, M., Motesharrei, S., Mu, Q., Kalnay, E., & Li, S. (2015). Local cooling and warming effects of forests based on satellite observations. Nature Communications, 6, 1–8.

Mykleby, P. M., Snyder, P. K., & Twine, T. E. (2017). Quantifying the trade-off between carbon sequestration and albedo in midlatitude and high-latitude North American forests. Geophysical Research Letters, 44(5), 2493–2501.

Waldron, A., Adams, V., Allan, J., Arnell, A., Asner, G., Atkinson, S., Baccini, A., Baillie, J. E., Balmford, A., Austin Beau, J., Brander, L., Brondizio, E., Bruner, A., Burgess, N., Burkart, K., Butchart, S., Button, R., Carrasco, R., Cheung, W., … Zhang, Y. (2020). Protecting 30% of the planet for nature: costs, benefits and economic implications.

Wenzel, L., D’Iorio, M., Wahle, C., Cid, G., Canizzo, Z., & Darr, K. (2020). Marine protected areas 2020: Building effective conservation networks.

Williams, C. A., Gu, H., & Jiao, T. (2021). Climate impacts of U.S. forest loss span net warming to net cooling. Science Advances, 7(7), 1–7.