Monday, June 3, 2024

June 2024 science summary

Long-horned bee (Melissodes) on sunflower


While I have heard that most of you want me to keep focusing on research articles (and I do have four this month, three on fire and one on pollinators), I also wanted to highlight two great books I've read.

First is "Eve: How the Female Body Drove 200 Million Years of Human Evolution" by Cat Bohannon. The intro has a really incisive indictment of how much biology research has centered on men, and how harmful that's been to both science and women in particular. It then delves into how and why various female traits evolved. I found it both fascinating and useful, and was shocked at how recent and limited efforts to better represent women in clinical trials have been. Here's a NYtimes review:

The other is About Us (, which is a collection of articles about many different forms of disability, each written by a person with lived experience (with one exception for people who are mostly unable to communicate, written by an ally). It seems like it would be a slog or a downer, but the articles are short, well-written, and really diverse in style which makes it a pretty quick and fun read (plus super educational). Some are funny, some made me cry (including some funny / sad mixes), but all were worth reading. If you are a New York Times subscriber all the component articles are free, but I liked having it in book form. If you're in DC and want to borrow a copy let me know!

If you know someone who wants to sign up to receive these summaries, they can do so at (no need to email me).

Li et al. 2024 is a methods paper about using land cover data to predict floral resource availability for pollinators. I'm an author despite minimal input; the lead author based this on work by the last author, who I provided some guidance to when he was a postdoc. There are a few potentially interesting things in here. 1) Most pollinators don't make much honey, so their populations are limited by the time of year w/ the least food available (pollen and nectar). The methods here help you figure out those bottlenecks if you want to target habitat restoration to boost pollinator populations. 2) Plants vary a lot in how much nectar pollen they make. Not every crop makes flowers that feed pollinators (likely obvious, but some crops and cover crops are harvested or terminated before flowering, and wind-pollinated plants don't have nectar). Trees produce a ton of nectar and pollen. 3) The paper looked at two different ways to map land cover, and surprisingly the simpler approach worked as well (similar error levels)! It's a good reminder to always question whether you need more complexity and accuracy.

I added some tips for improving pollinator habitat in your own garden here.

Parks et al. 2023 looks at severity and frequency of fire in dry conifer forests in the Western US (see Fig 1), comparing the last 40 years to pre-colonial times. They found that forests that kill most or all trees ("stand-replacing fires") are from 3 to 14 times more common now (varying by ecoregion). By looking at areas with varying logging pressures and fire suppression, they show that logging is not reducing stand-replacing fires, but places w/ more prescribed fire and the least fire suppression have much less of these severe fires. For example, in the Gila Wilderness (where many fires are not suppressed) the % of fires that were stand-replacing was 3 times lower than the ecoregion it's in. Prescribed fires consistently led to the lowest stand-replacement, at similar rates to pre-colonial times. Fig 4 and 5 have some great aerial images of forests before and after fire and changes over decades.

Peeler et al. 2023 is an analysis of the best places in 11 US Western states for coniferous forest management (removing small trees and brush, and/or prescribed fire) to reduce the risk of wildfire leading to carbon loss (and/or to protect human communities). Skip to Fig 5 for the key results (the highest ranked places they found) and Fig 3 for more detail. Note that they excluded forests which historically burned rarely b/c ecologically these kinds of forests are supposed to be dense and thinning would alter that ecology (but they still see a role for prescribed fire and tree planting there). They also flag the need for cross-boundary collaboration (including w/ local & Indigenous knowledge and values).

Vidal-Riveros et al. 2023 looks at wildfire history and impacts across the Gran Chaco region (see Fig 1 - it's mostly in Argentina and Paraguay with some in Bolivia and a tiny bit in Brazil, and includes two ecoregions). It's a good review, but they note that the literature has some big gaps. It is mostly focused in Argentina (69% of papers they assessed) with only 10% in Bolivia and 3% in Paraguay. 68% of the papers were on remote sensing of fire frequency, most of which lacked field calibration and validation (which is really important). Unsurprisingly cattle ranching is the main source of wildfire, and in many cases is frequent enough to make it hard for vegetation to recover. For example, in Bolivia 4 yr burning cycles don't allow for forest and soil regeneration, while leaving land fallow for 14-20 years after fire (in Argentina) promotes plant diversity and weed control. The paper has some good info on how different plant species and communities respond to fire. It notes there's limited info on how fire affects invasive non-native plants, but one study in Argentina found prescribed fire killed native and non-native species at similar levels (and some highly flammable non-native spp promote flame spreading). Fig 3 has a nice model of how fire and grazing interact to shape whether grass or trees or shrubs dominate in a given place.

Li, K., Fisher, J., Power, A., & Iverson, A. (2024). A map of pollinator floral resource habitats in the agricultural landscape of Central New York. One Ecosystem, 9.

Parks, S. A., Holsinger, L. M., Blankenship, K., Dillon, G. K., Goeking, S. A., & Swaty, R. (2023). Contemporary wildfires are more severe compared to the historical reference period in western US dry conifer forests. Forest Ecology and Management, 544(June), 121232.

Peeler, J. L., McCauley, L., Metlen, K. L., Woolley, T., Davis, K. T., Robles, M. D., Haugo, R. D., Riley, K. L., Higuera, P. E., Fargione, J. E., Addington, R. N., Bassett, S., Blankenship, K., Case, M. J., Chapman, T. B., Smith, E., Swaty, R., & Welch, N. (2023). Identifying opportunity hot spots for reducing the risk of wildfire-caused carbon loss in western US conifer forests. Environmental Research Letters, 18(9), 094040.

Vidal-Riveros, C., Souza-Alonso, P., Bravo, S., Laino, R., & Ngo Bieng, M. A. (2023). A review of wildfires effects across the Gran Chaco region. Forest Ecology and Management, 549(September), 121432.

p.s. This is a photo of a long-horned bee (Melissodes spp.) which I only ever saw in my garden the one year I grew a couple sunflowers. They look even cooler close up: photo 1photo 2, photo 3

Monday, May 20, 2024

Pollinators - new paper and tips for your garden

Bumblebee on blueberry flowers

I wanted to announce a new paper I've been kindly included as an author on (despite minimal contributions) - Li et al. 2024. It's a methods paper about using land cover data to predict floral resource availability for pollinators. There are a few potentially interesting things in here. 1) Most pollinators don't make much honey, so their populations are limited by the time of year w/ the least food available (pollen and nectar). The methods here help you figure out those bottlenecks if you want to target habitat restoration to boost pollinator populations. 2) Plants vary a lot in how much nectar pollen they make. Not every crop makes flowers that feed pollinators (likely obvious, but some crops and cover crops are harvested or terminated before flowering, and wind-pollinated plants don't have nectar). Trees produce a ton of nectar and pollen. 3) The paper looked at two different ways to map land cover, and surprisingly the simpler approach worked as well (similar error levels)! It's a good reminder to always question whether you need more complexity and accuracy.

I was asked "How can we use these insights in NYC if at all for urban pollinator husbandry?" which made me realize I should have been more clear about tips for people who want their gardens to better support pollinators.

The actual results are specific to upstate New York and wouldn't apply elsewhere. To make this work one of the authors had to visit many places to see what plants were blooming in what kinds of habitat at different times, then use remote sensing to make a land cover map, then do the math to see when floral resources are scarce.BUT here's how I have been using the very rough concept it in my own garden!

1. Take notes and photos throughout the year as you walk around your neighborhood. When do you first see bees (and/or other pollinators like flies and beetles), and what flowers are they visiting? If you're not seeing bees in your garden - try planting those early bloomers in your own yard.

2. What weeks do you notice the most and least flowers? This isn't a perfect proxy since some flowers have big petals but don't provide much food (like marigolds, geraniums, lilies, and tulips). But it's a start. Write down the weeks where you see the fewest flowers in the neighborhood. That tells you where your garden can have the most added value.

3. Are there certain plants absolutely mobbed with pollinators certain weeks (bees, flies, moths, etc.)? That's a good clue they may be offering food when it's scarce, and/or it's high quality, and you could plant more of them. If you want diverse pollinators, include some plants with small composite flowers (I find those are the most popular overall, especially for sweat bees and bomber flies, something like anise hyssop / Agastache or goldenrod) and some with bigger flowers larger bees like (Penstemon is a favorite of my bees, although the bees also love basil flowers).

4. Based on your notes, add perennial plants that flower when there are the fewest available flowers in the neighborhood. For me that was early spring, late fall, and mid to late summer. Consider also adding some plants that flower intermittently year round like rosemary - it's consistently a star performer in late winter / early spring for me, but also gets some love in the summer. For folks in the DC area my top performers are probably penstemon, anise hyssop, goldenrod, swamp milkweed, and obedient plant (for late fall / early winter)

5. Take notes and/or photos of what you see in your garden. It's fun to see how specific flowers will attract species that won't come otherwise. Use Google Lens or iNaturalist to identify at least the rough kinds of bees. Look for the metallic green or orange Agopostemon bees, get close photos of sweat bees, and whatever other ones surprise you. Here are my pics of pollinators in my garden.

6. Experiment! One year I planted sunflower and it was the only time I saw a long-horned bee in my garden (check out the pics: it's a pretty cool bee). I used to have some lambs ear which I got rid of b/c it wasn't native, but then I stopped seeing carder bees (which collected its fuzz).

7. Leave the dead flower stems through the winter; when new shoots and leaves form on the plant, break off the stems at different heights and toss them elsewhere in your garden (not compost). Many bees and other pollinators lay their eggs in the stems and you don't want to get rid of them before they hatch. See this guide from Xerces for more.

8. Have fun. It's really cool to see how much impact you can have on your garden and neighborhood.

9. Don't forget about habitat for other wildlife! My favorites: 

a) add a birdbath if you're able to commit to dumping and replacing the water daily (you can use rain barrel water like I do). Scrub it with a brush weekly. Get one w/ rough iron sides or leave in a stick so bugs can drink but escape if they fall in.

b) make sure you have some bushes for birds to hang out in. Mine love the swamp dogwood and viburnum more than the inkberries I planted specifically for birds.

c) if you're in the Mid-Atlantic, plant cut-leaf coneflowers. You get 7-8' tall plants that attract so many goldfinches that eat the seeds!

d) let some of your herbs flower. In addition to bees loving basil, cardinals love coriander seeds from cilantro!

e) pokeweed is a native aggressive perennial that provides so much free bird food, especially to catbirds but also robins and mockingbirds and sometimes other species. Cut it back or dig it up when it spreads too much.

e) if you have room, make a brush pile from any pokeweed stems and woody stems and bush trimmings. Several species appreciate them.

f) I used to think "certified wildlife friendly" signs were silly and bragging, but then I heard some neighbors walk by complaining about how unruly my garden was (they didn't see me on the porch). I ordered a sign, and a week or so after I put it up, I heard the same neighbors walk by, see the sign, and say "oh that's cool! it's a wildlife-friendly garden!" So it's worth looking into and the process has a few more tips.

Wednesday, May 1, 2024

May 2024 science summary

Blackwater River trail


This month I have a mixed bag of four unrelated articles: the efficacy of conservation globally, the state of wetlands in the US, the state of the world's migratory species, and one on how biodiversity relates to productivity in forests.

If you know someone who wants to sign up to receive these summaries, they can do so at (no need to email me).

Langhammer et al. 2024 is the big splashy new Science paper looking at the impact of conservation. It's a meta-analysis of trials comparing interventions to counterfactuals (similar areas w/o action). They found conservation helps 2/3 of the time (45% of trials led to absolute improvement in biodiversity, 21% reduced biodiversity loss), but is harmful 1/3 of the time (in 21% of trials biodiversity declined more due to conservation, in 12% it improved less due to conservation), and only 2% of trials showed no difference). That's not a great track record - I'd hoped net harm would be rare (1/3 is very high!), and just over half the time we're losing biodiversity despite trying to stop it. Fig 2 helpfully shows how impact varies by type of intervention: protected areas show the smallest positive effect on average, and invasive species removal shows the largest positive effect. I'd ignore "sustainable use of species" b/c it's a weirdly broad category that somehow only included 4 papers on wildlife hunting and 1 on fishing, although a few fishing papers are included under protected areas (details in the supplement - this makes me think their sample is not representative of conservation broadly). While the authors conclude conservation is working and we should do more of it, I bet if this was a paper on medical efficacy we'd consider interventions that are 2/3 helpful and 1/3 harmful an urgent cry to improve efficacy BEFORE we try to scale work that is so often ineffective or harmful. Would you send your kids to a school where 1/3 of students learned less than kids not in school at all?

The latest report on the status of wetlands in the US (excluding AK and HI) is a bummer but has some useful info. Key summaries are in Fig 9 and Table 2, but in short on net 221,000 acres of wetlands were converted, mostly to ag and tree plantations followed by housing developments. But that net change hides that fact that we actually lost 670,000 acres of vegetated wetlands, with non-vegetated wetlands like ponds, sandbars, and mudflats increasing (but NOT providing nearly as much ecological value). The report calls for more coordination to achieve no net loss of wetlands, to update and improve the National Wetlands Inventory, develop and implement better wetland conservation and management (duh), and commit to long-term monitoring and adaptive management.

The new State of the World's Migratory Species report (UNEP-WCMC 2024) has an update on how the 1,189 migratory species in CMS are doing. Almost half (44%) are in decline (with 22% at risk of extinction, including 97% of listed fish spp), 1/3 are stable, and the rest are split between improving and unknown. The report also notes that 399 spp not even listed in CMS (including ~200 fish spp, ~150 bird spp, and ) are at risk (from critically endangered to near threatened). See Fig 2.10b for an overview of which migratory species CMS leaves out (including horseshoe crabs!) and 2.10c for the subset at risk. Unsurprisingly the main threats are habitat loss (along w/ degradation and fragmentation) and overexploitation (hunting and fishing). Recommendations on page ix-xi are familiar and unsurprising (albeit important). There's a blog about this paper with key highlights at:

At first I thought Liu et al. 2024 was saying that productivity (the rate at which biomass is created) is a great predictor of forest species richness / biodiversity. That's not right though! Look at Fig 2 - they're actually saying that to predict productivity there is a significant but weak positive correlation to tree species richness, which is about the same as the correlation w/ more compelx metrics (functional attribute diversity and phylogenetic diversity). But forest stands under 30 show lower productivity with higher richness, and wildlife richness is left out entirely. So this is less of a strong & clear relationship, and more of a "if you're going to compare the two you may as well use the simpler metric" result.


Lang, M. W., Ingebritsen, J. C., & Griffin, R. K. (2024). Status and Trends of Wetlands in the Conterminous United States 2009 to 2019. U.S. Department of the Interior; Fish and Wildlife Service, Washington, D.C. 43 pp.

Langhammer, P. F., Bull, J. W., Bicknell, J. E., Oakley, J. L., Brown, M. H., Bruford, M. W., Butchart, S. H. M., Carr, J. A., Church, D., Cooney, R., Cutajar, S., Foden, W., Foster, M. N., Gascon, C., Geldmann, J., Genovesi, P., Hoffmann, M., Howard-McCombe, J., Lewis, T., … Brooks, T. M. (2024). The positive impact of conservation action. Science, 384(6694), 453–458.

Liu, Y., Hogan, J. A., Lichstein, J. W., Guralnick, R. P., Soltis, D. E., Soltis, P. S., & Scheiner, S. M. (2024). Biodiversity and productivity in eastern US forests. Proceedings of the National Academy of Sciences, 121(14), 2017.

UNEP-WCMC, 2024. State of the World’s Migratory Species. UNEP-WCMC, Cambridge, United Kingdom.


p.s. This photo is on the Blackwater River Trail in the Canaan Valley Resort State Park, where we were treated to some April snow on vacation!

Monday, April 1, 2024

April 2024 Science Summary

Art at the Kennedy center


Just three articles this month: how wetland restoration affects climate mitigation, how climate change is affecting seasonality of river flow, and a summary of how people use plants around the world.

If you know someone who wants to sign up to receive these summaries, they can do so at (no need to email me).

Schuster et al. 2024 reviews the net climate impact of wetland restoration, considering carbon, methane, and nitrous oxide. Their headline is that it takes 525 years for restoring peat to result in net climate cooling (b/c short-term methane increases offset the carbon gains), and 141 years for non-peat wetlands (marshes, riparian wetlands, and swamps). They argue other more positive estimates have left out nitrous oxide. BUT they are looking just at the restoration over time NOT comparing restored wetlands to the baseline of degraded wetlands (since drained peat also emits methane and lots of CO2, the time would be a lot shorter to be net climate cooling. Some other papers I've read (e.g., Richardson et. al 2022 on pocosin) found minimal methane emissions making restoration a clear winner even in the short term. I asked a couple experts about this paper and they also flagged that while in the short term we should be worried about methane, it's also true that: the alkalinity export from peat could make them MORE cooling than we think, and that there are other ecosystem services to consider.

Wang et al. 2024 looks at how climate change has changed the seasonality of river flow (how much it varies month to month, including frequency of droughts and floods). They found that ~14% of long-term river gauges show changes in seasonality over the last 50 years that isn't driven by changing annual precipitation. The surprise is that seasonality is mostly DECREASING counter to the narrative of more floods and droughts (see Fig 1 for a map of results, and Fig 2 which adds detail). In their figures brown means less seasonality (more even flow): "L+" means low flows become higher flows (NOT higher frequency of drought) while "H-" means floods see lower flood volume (again NOT lower frequency of flood events). You'll see most of North America, most of Europe, and some of Russia have seen reduced seasonality in recent decades. Blue means MORE seasonality, focused in: SE Brazil, some European countries, and in the US the SE and some of the Rocky Mountains. The explanation is worth reading in full, but in brief: 1) snow melting earlier means less runoff from snow at the same time as spring rains, 2) early spring greening means more water gets transpired, 3) it's more complicated in places not dominated by snowmelt.

Pironon et al. 2024 is a global analyis of plants used by humans (directly or indirectly - medicinal uses dominate but they look at nine other types of use, see Fig 2). See Fig 1a for a map of how many plant species are used around the world. They find 1) people use more plant species in places where most plant species exist, 2) Indigenous lands use slightly fewer species than neighboring non-Indigenous regions, and 3) protected lands use slightly fewer species than non-protected lands. These are correlations - they don't control for income or many other covariates. And from a conservation perspective we may not want all species to be used, especially rare ones!Note there are some problems with the data, e.g., Figure S1 shows how poor the sampling density is outside of the US, Central America, Europe, and Australia. Finally, they only found 971 species of plants that provide food to bugs we use (honeybees, silkworms, lac insects, and grubs) which seems really low. There's an article about this at:

Pironon, S., Ondo, I., Diazgranados, M., Allkin, R., Baquero, A. C., Cámara-Leret, R., Canteiro, C., Dennehy-Carr, Z., Govaerts, R., Hargreaves, S., Hudson, A. J., Lemmens, R., Milliken, W., Nesbitt, M., Patmore, K., Schmelzer, G., Turner, R. M., van Andel, T. R., Ulian, T., … Willis, K. J. (2024). The global distribution of plants used by humans. Science, 383(6680), 293–297.

Schuster, L., Taillardat, P., Macreadie, P. I., & Malerba, M. E. (2024). Freshwater wetland restoration and conservation are long-term natural climate solutions. Science of The Total Environment, 922(August 2023), 171218.

Wang, H., Liu, J., Klaar, M., Chen, A., Gudmundsson, L., & Holden, J. (2024). Anthropogenic climate change has influenced global river flow seasonality. Science, 383(6686), 1009–1014.

p.s. This photo is of a sculpture at the Kennedy Center by ByeongDoo Moon called "I have been dreaming to be a tree"

Friday, March 1, 2024

March 2024 science summary



This month I have two articles on wildlife connectivity, one on global groundwater depletion, one on scientific reproducibility, and one on organizational behavior change.

If you know someone who wants to sign up to receive these summaries, they can do so at (no need to email me).

Scientists often complain policy makers don't follow our recommendations (or even read them). But Brisco et al. 2023 finds that recommendations from meta-analyses tend to change over time as research continues. They looked at 79 papers (121 meta-analyses) and found that over time 93% of analyses either had a big change in effect size (+- 50% or more, see Fig 2 for examples) or change in statistical significance (see Fig 3). The key results are in Fig 5, which I find pretty confusing. Results staying consistently statistically significant w/ each study is rare, and ~25% of analyses showed a reversal in effect (from positive to negative or vice versa). Those reversals are the change we care the most about since it means action can backfire. BUT if you ignore the studies that were never statistically significant (seems safe) it's only 12% of analyses that flip, and if you also ignore the ones that lost significance (meaning the reversal is less meaningful) it goes down to 11%. That's still pretty bad though - 1 time out of 9 the scientific recommendation might lead to the opposite outcome we intend. They recommend scientists use cumulative meta-analyses to look for trends, and the reminder that we're often wrong reinforces the need for adaptive management and an empirical approach to seeing what works in a given context.

Jasechko et al. 2024 is a global assessment of groundwater levels since 2000 (using 170,000 wells and 1,700 aquifers) and comparing them to earlier trends for ~1/3 of those aquifers. They found 36% of aquifers were drying up (water level dropping deeper by 0.1 m / yr or more), and 6% of aquifers were improving (water level rising 0.1 m / yr or more), w/ 58% of aquifers not changing quickly in this century. 30% of the aquifers where they had 40 years of data declined faster in the 21st century than the 20 years prior (see Fig 3), but in 49% of those aquifers declines slowed or reversed. Unsurprisingly the trend is worst in drylands w/ farmland, and groundwater deepening is globally correlated w/ low precipitation, high evapotranspiration, and extent of agriculture. See Fig 1 and 2 for global map of trends, highlighting hotpsots of decline in CA, the US high plains, Iran, India, central Chile, and a few others. There's a news article about the study at

Iverson et al. 2024 cautions against assuming that modeled wildlife corridors connecting habitat patches ('linkages') actually receive much heavier use by wildlife. They looked at five linkage models in CA (see Fig 1), and compared them to 1) wildlife-vehicle collisions and 2) modeled wildlife presence (from a large set of wildlife observations). While black bear and puma vehicle collisions were slightly more likely in linkages, racoon collisions were LESS likely in linkages, and the other five species assessed were mixed depending on model. Across all eight species no model did consistently well for either wildlife vehicle collisions nor modeled occupancy. The authors note that the linkage models were all built on human disturbance metrics, but that another study found those metrics only significantly drove away about 1/3 of mammal species studied (including big carnivores and omnivores). Since wildlife don't have apps to find optimal travel routes, it's not shocking that they're not heavily using linkages. But this study is a good reminder to be wary of relying on models for citing narrow corridors, and it's a safer bet to assume wildlife presence is not typically highly concentrated.

Thurman et al. 2024 argues that it's important to consider disease when doing conservation planning and wildlife management. One key point is that in some cases improving connectivity can be net harmful for some species. The case of prairie dogs and black-footed ferrets on the top of page 3 is fairly compelling (the impact of plague is high enough that mitigating its spread should be a priority). Overall, I think it's fair to say that species and ecosystems need climate-resilient connectivity options to adapt to climate change, even if increased disease transmission offsets the benefits somewhat. But thinking about disease and if/how to incorporate it in planning should always be a good idea. I like the orange questions in Figure 1, but found the longer list in Table 1 to be overwhelming (which could make it harder for planners to act). There's no silver bullet being offered here, but maybe they're warning us to watch out for 'friendly fire' (unintended negative impacts of promoting connectivity w/o thinking about disease).

Ferraro et al. 2019 is a non-peer-reviewed working paper that asks whether behavioral psychology nudges known to influence individuals work on organizations too. They looked at a national organization asking for voluntary membership does from 3,000 nonprofits, and tested 1) crafting a clear and salient ask to emphasize public benefits, 2) publicly sharing who contributed and by how much, and 3) showing quarterly progress towards a national goal. All had no effect (each treatment on average made contributions very slightly lower, but w/o statistical significance). The authors hypothesize (w/ evidence from other studies) that group decision making makes orgs less responsive than individuals to these kinds of interventions. An interesting follow-up study would be to target individuals with the individual authority to make decisions that affect the broader organization and see if that works.


Brisco, E., Kulinskaya, E., & Koricheva, J. (2023). Assessment of temporal instability in the applied ecology and conservation evidence base. Research Synthesis Methods, November, 1–15.

Ferraro, P. J., Weigel, C., An, J., & MESSER, K. D. (2019). Nudging Organizations: Evidence from three large-scale field experiments (Vol. 21211).

Iverson, A. R., Waetjen, D., & Shilling, F. (2024). Functional landscape connectivity for a select few: Linkages do not consistently predict wildlife movement or occupancy. Landscape and Urban Planning, 243(March 2023), 1–12.

Jasechko, S., Seybold, H., Perrone, D., Fan, Y., Shamsudduha, M., Taylor, R. G., Fallatah, O., & Kirchner, J. W. (2024). Rapid groundwater decline and some cases of recovery in aquifers globally. Nature, 625(7996), 715–721.

Thurman, L. L., Alger, K., LeDee, O., Thompson, L. M., Hofmeister, E., Hudson, J. M., Martin, A. M., Melvin, T. A., Olson, S. H., Pruvot, M., Rohr, J. R., Szymanksi, J. A., Aleuy, O. A., & Zuckerberg, B. (2024). Disease‐smart climate adaptation for wildlife management and conservation. Frontiers in Ecology and the Environment, 1–10.

p.s. The photo is of a piece called "Shift" by Lisa Wood Studios, and it cycled between saying "Unconscious consumption" and "Conscious conservation" (presumably what we have now) and then as shown above "conscious consumption" and "unconscious conservation" (which makes less sense to me, but presumably means we're mindful of our choices and conservation happens automatically?

Thursday, February 1, 2024

February 2024 science summary

Snowflake ornament illuminated by Christmas tree lights


This month is a bit of a grab bag again with an article on freshwater protection, another on koala-vehicle strikes, and two on soil carbon (both offering caution on the potential and flagging complexity).

If you know someone who wants to sign up to receive these summaries, they can do so at (no need to email me).

Flitcroft et al. 2023 notes that counting effective freshwater protection globally is really hard (as is getting effective protection to happen). Fig 1 has a nice summary of how restrictive different protection mechanisms are. They also call for both better management of existing protected areas (PAs) to include freshwater conservation needs, and protections for freshwater in new places. While issues around data resolution and data availability continue to pose challenges to freshwater conservation, they argue that more explicit consideration of both freshwater and terrestrial objectives in any area-based protection is a good start.

Dexter et al. 2023 makes a point that seems obvious once you think about it, but which was new to me. Namely, hotspots of wildlife-vehicle collisions (they looked at koala strikes) are likely to be very dynamic over time as wildlife populations grow and shrink, as land use change drives shifts in their movement, and as roads and traffic change. They make the point that wildlife crossings are generally cited based on past collision data, and found that collision hotspots decline over time (as nearby populations decline and/or move). There was some unspecified 'road mitigation' which could have partially driven the reductions but the authors said the mitigation wasn't sufficient to explore the decline (pointing to unpublished data, unfortunately). They recommend instead taking a broader landscape approach considering habitat and trends as opposed to focusing crossings at local collision hotspots, and including crossings or other mitigation early when making infrastructure changes.

Ogle et al. 2023 looks at the soil carbon portion of U.S. plans to meet their contribution to the Paris agreement on climate mitigation. They review several well known challenges w/ soil carbon (C): changes are hard to predict and measure accurately, that additionality and permanence can be challenges, and that changing practices can have undesirable side-effects (increasing emissions from soil of strong GHGs like nitrous oxide or methane, shifting emissions to other farms, etc.). See Table 1 for a summary. They also provide an overview of policy options including mandates, subsidies and incentives, C taxes, and C offsets (see Table 2). They call for a suite of research to investigate these challenges and look for a path forward if one exists.

Wang et al. 2023 is a helpful review of the degree to which soil carbon sequestration can offset greenhouse gas (GHG) emissions from ruminants (mostly cattle, but also sheep, goats, and buffaloes). It's a nice example of fairly simple analysis revealing important insights. Their top level finding is that to offset ruminant emissions from manure and burping over a 100 year timeframe, we would need to roughly triple the current total global carbon stock in managed grasslands (adding 200% to existing stocks), with regional increases needed from ~25%-2000% (Fig 4b, and see 4c which is per ha). That large an increase is not feasible; while reducing net emissions on ranches is important, we shouldn't expect to get the global beef & other ruminant sector to help mitigate climate change on net. That's perhaps obvious, but fringe local cases of low-density ranches w/ lots of nature potentially being carbon negative are often cited as examples of something globally scalable, so it's a useful reminder that they are not unless we reduce the global supply of ruminants (farm and eat less of their meat and dairy). Fig 3 summarizes how cattle factor into this in a different way: depending on how a given grassland can sequester and how much methane each cow produces, the "offsettable" cattle density ranges from 0 to 1.2 (for the very best case scenario).

Dexter, C. E., Scott, J., Blacker, A. R. F., Appleby, R. G., Kerlin, D. H., & Jones, D. N. (2023). Koalas in space and time: Lessons from 20 years of vehicle‐strike trends and hot spots in South East Queensland. Austral Ecology, June 2021, 1–18.

Flitcroft, R. L., Abell, R., Harrison, I., Arismendi, I., & Penaluna, B. E. (2023). Making global targets local for freshwater protection. Nature Sustainability.

Ogle, S. M., Conant, R. T., Fischer, B., Haya, B. K., Manning, D. T., McCarl, B. A., & Zelikova, T. J. (2023). Policy challenges to enhance soil carbon sinks: the dirty part of making contributions to the Paris agreement by the United States. Carbon Management, 14(1).

Wang, Y., de Boer, I. J. M., Persson, U. M., Ripoll-Bosch, R., Cederberg, C., Gerber, P. J., Smith, P., & van Middelaar, C. E. (2023). Risk to rely on soil carbon sequestration to offset global ruminant emissions. Nature Communications, 14(1), 7625.
p.s. This is a photo of a handmade glass snowflake ornament reflecting and transmitting several colors of Christmas tree lights

Thursday, January 25, 2024

Best of 2023 science summaries

Luna resting her head on Kong (on Jon's lap)

Happy new year!

As usual here are my favorite 15 articles from 2023, and a few other things you may have missed.

But first - if you or someone you know are looking for a sweet and loving dog in your life (or two?), both of our foster dogs Luna (top head above) and Kong (supporting head) are still up for adoption! You can read about Kongsee how cute he isread about Luna, and see how cute she is.

  1. A summary of the IPCC's latest report (AR6) came out, click here for my brief summary of that summary
  2. The earth had its first day that was 2C warmer than the historic pre-industrial average (1850-1900). We're still a ways from an AVERAGE of 2C warmer than pre-industrial, but still a bummer.
  3. Last month I shared some (not very well-informed) thoughts about how I'm using artificial intelligence (AI), specifically large language models (LLMs) like ChatGPT and Google's Bard. Scroll to the bottom of my December summary  to see them

On to the science articles!

Chaplin-Kramer et al. 2022 is a great global summary of 14 ecosystem services I've been waiting to see for years! Their big finding is that 90% of nature's local contributions to people within each country come from a total of 30% of global land area and 24% of coastal waters (EEZs). Globally only 15% of those places are protected. The land and water needed is uneven by country (e.g., the US needs 37% of land and 15% of coastal waters), and protection varies too. See Fig 1 for the areas that provide the most benefit per unit area. The land required would be lower if optimizing globally, but at the cost of less equitable benefit distribution. The 2 global ones (carbon storage and moisture recycling) need 44% of land (optimized globally) to stay at 90% of current levels, mostly overlapping with the 30% (see Fig 3). Roughly 87% of the world population benefits from at least one of the ecosystem services, but benefits are not distributed equally (see Fig 2). The local services include: water quality (regulating nitrogen and sediment), crop pollination, livestock fodder, production of timber and fuelwood, flood regulation, fish harvest (from rivers and oceans), recreation (on land and oceans), and coastal risk reduction. If interested you can get combined GIS data from or one of the authors (Rachel Neugarten) is happy to send individual maps and data.

Cinner et al. 2019 is a 16 year study of rotational fishing / closure in Papua. They found success in compliance with the system (due to strong social cohesion driven by leaders sharing info, a "carrot and stick" approach, and lots of community participation) BUT even though closed areas rebounded, over the study period fish biomass dropped by about half. So even though the closure program worked as intended, it wasn't enough to offset overfishing when areas were open.

Grenz & Armstrong 2023 is an article criticizing "pop-up restoration," a term they coin for ecological restoration that 1) lacks long-term engagement and monitoring, 2) denies people use of lands (even Indigenous people who have been there for millennia), and 3) sets fixed ecological baselines or goals even for ecosystems which historically were highly managed and dynamic. They describe two use cases where  management outcomes preferred by Indigenous people were ignored, instead managing for outcomes preferred by non-Indigenous ranchers or residents. They call for restorative justice being the norm, and ethical engagement with communities in each specific place (rather than coopting and misusing Indigenous knowledge). They also call for more openness to evolving needs and conditions of both people and ecosystems, and acknowledging failures and wrongdoing.

James et al. 2023 asked over 900 science & conservation staff of The Nature Conservancy about their careers and influence, and how they perceived their gender as impacting that. We found that women had less influence, experienced many barriers to their careers (including harassment, discrimination, and fear of retaliation for speaking out), and that men overestimated gender equity. Only have 5 minutes? Skip to the recommendations on page 7 (we ask orgs to: show public leadership on equity, improve transparency and accountability, diversify teams and improve career pathways for women, be flexible, include training and mentoring as part of broader change, help women connect, address sexual discrimination and harassment, and consider intersectionality). If you have 15 minutes more, read the quotes in Table 2 (p5-8) because they're really compelling and illustrative. Or if you're with the half of men and 3/4 of women in our sample who think we have more to do on gender equity (rather than that we've already "gone overboard" or that it's not an issue as some men reported), just read the whole damn paper because there's a lot of interesting detail and nuance in the results. I learned a ton while helping out on it, and I'm excited to start advocating for the recommendations. You can read it at: or a short blog at 

Toomey et al. 2023 is a nice reminder that just sharing information doesn't usually change minds. They challenge the idea that facts & scientific literacy lead to research being applied, and that broad communications targeting as many individuals as possible are the most effective way to share those facts. Instead they recommend appealing to values and emotions, and strategically targeting audiences by considering social networks (drawing on science about behavior change) and social norms. I love the conclusion that "this article may not change your mind" but that they hope it will inspire reflection. I also like the use of the backronym WEIRD (Western, Educated, Industrialized, Rich, Democratic) to describe countries like the US.

Dickson et al. 2023 piqued my curiosity by breaking down different causes of conservation failure and how to respond. I generally dislike taxonomy papers, and find them academic and hard to apply. But understanding how to respond to different kinds of failure seems helpful, especially for the most common causes (including lacking a sufficiently robust theory of change. see table 2 for more). Their taxonomy has 59 (!) root causes, grouped into 6 categories: 1) planning, design, or knowledge (e.g., inadequate theory of change); 2) team dynamics (e.g., disagreements on what priorities should be); 3) project governance (e.g., lack of a technical advisory group); 4) resources (e.g., staff overloaded or lack needed technical expertise); 5) stakeholder relationships (e.g., lack of buy-in from gov't); and 6) unexpected external events (e.g., natural disaster, war, disease, etc.). After reading all the ways to fail, my main take away is that failure will happen sometimes and we need to focus on how to learn and pivot. The other big one is that while teams often resent spending a few hours developing and refining a theory of change (ToC), that is likely time well spent given that how often an insufficient ToC was listed as a cause of failure.

Duncanson et al. 2023 estimates how much global forested protected areas may be reducing climate change. They matched forested protected areas to similar forested unprotected areas using data from 2000 (land cover, ecoregion, and biome; with additional control pixels that accounted for population etc. - see Table S1). Then they used the new (2019) GEDI lidar data to estimate aboveground forest biomass in 2020. 63% of forested PAs had significantly higher biomass than matched unprotected areas; on average PAs have 28% more aboveground biomass. Over a third of that effect globally comes from Brazil; Africa had less C dense forests and more human pressures on both PAs and unprotected areas. As you'd guess, most of the difference in unprotected sites was due to deforestation. But in 18% of PAs carbon was higher than unprotected sites even though optical sensors didn't detect deforestation (implying LiDAR is detecting either avoided degradation and/or enhanced growth in PAs). As a final note, other research has shown that both ICESat-2 and GEDI LiDAR satellites tend to underestimate forest canopy heights (mostly irrelevant here given the matching approach, but good to know for other global estimates).

Knauer et al. 2023 has good news - better modeling estimates forests could sequester more carbon than we thought. But it's likely very small good news. Their best case is 20% more "gross primary productivity" (GPP, energy captured by photosynthesis), BUT a) that's using an extremely unlikely 'worst case' cliamte scenario which is actually hard to achieve, (RCP8.5) and b) only a fraction of GPP ends up sequestered as carbon (see Cabon et al. 2022 for more). Since forests offset roughly 25% of annual human emissions, the results likely mean <1% of annual emissions could be offset. I'll take it, but we still need to reduce gross emissions as fast as possible.

Rubenstein et al. 2023
 is a systematic review of how documented range shifts (when plants and animals change where they live, presumably in response to climate change) compare to predictions. Across 311 papers, only 47% of shifts due to temperature were in expected directions (higher latitudes & elevations, and marine movement to deeper depths was seen but was non-significant). See Fig 4 for how results varied by taxonomic group, ecoystem type, and type of shift. Not many studies looked at precip but of those that did only 14% found species moving to stay in a precip niche. Note: this means simple assumptions of how species will move are of limited value, but NOT that local or regional predictions are inherently flawed. The authors note that considering local predictions of changing temp and precip will often depart from these simple assumptions, and other factors like water availability, fire, etc. are likely to be relevant. A final note on the last page was helpful: not all range shifts have equal relevance to management. In some cases a few individuals are moving to new places but most of the wildlife population doesn't shift at all. Both shifts AND non-shifts have implications for how management should change to keep species and ecosystems healthy! This paper has a LOT of nuance and variation in this paper, and a very detailed methods section with good recommendations for how scientists should continue these investigations

Dethier et al 2023 (briefly summarized in Walmsley 2023) finds that mining in tropical countries is dramatically increasing sediment in rivers. 80% of the 173 rivers affected by mining that they studied had sediment concentrations more than double what they were prior to mining. This is a pretty coarse estimate using satellite data, so the actual sediment estimates are very rough, but the general pattern should be valid.

NatureServe's 2023 Biodiversity in Focus US report is a high level look at threatened species (imperiled or vulnerable) in the US. It's short and worth reading the whole thing. They find 34% of plant species and 40% of animal species are threatened, and 41% of the ~400 ecosystem groups in the US are at risk of "range-wide collapse" (meaning being replaced or substantially transformed). Figure 1 and 2 have breakdowns of averages for plants and animals by subgroups. For plants cacti are the worst off at 48% threatened and sedges are the least threatened at 14%. Freshwater snails are the most threatened animals (75%, and other FW groups are all more threatened than average) while birds are the least threatened (12%) and bees are about average (37%). Note that % of species that are threatened is different than looking at % of individual organisms or biomass that is threatened (all are useful metrics, Audubon's State of the Birds report looks at trends in bird population size). Figure 3 shows the most and least threatened ecosystems; unsurprisingly virtually all tropical ecosystems are threatened (they had relatively small extents originally, and are valuable for agriculture), while cliffs / rock and alpine and tundra ecosystems fare the best due to less threat of conversion to other land uses and higher rates of protection (Figure 5). They don't provide details but I would guess these are relatively short-term predictions, as climate change will threaten a lot of alpine and tundra ecosystems in the long term. Figure 4 shows how protected different species groups and ecosystems are. Almost 30% of vascular plant species are protected >50% of their range, but only 15% of vertebrate species are that protected. Finally, Figure 9b shows which states have the highest % of their area in at-risk ecosyetsms (NE, MT, and SD score the highest due to large at-risk grasslands), and Figure 11 shows priority areas for conserving imperiled species. With some exceptions (like FL) Figures 9 and 11 highlight different priority areas; Fig 11 focuses on relatively small and irreplaceable places that the most threatened species rely on, while Fig 9 focuses on more intact and lower diversity ecosystems that are at risk of being transformed (but with less potential for species extinctions). The authors conclude that the Restoring America's Wildlife Act (RAWA) guided by State Wildlife Action Plans (SWAPs) is our best bet to catalyze massive investment in conservation of the places that need it most.

Jewell et al. 2023 surveyed directors and board members in charge of state wildlife agencies in the SE U.S. about future conservation challenges and how they plan to respond. They found that the respondents were focused on funding and 'agency relevance' (including changing values and fewer hunters) but less concerned about climate change (see Table 2). One quote stuck out at me, which was that they saw climate change impacts as important at time-scales beyond decades, and thus not urgent to act on (they also saw it as too political). By comparison, they saw education and outreach as critical to recruit hunters and tell the public the value of hunting and fishing. Agency directors average 5 years in office, so short-term things they can do may be more appealing. The authors call for engaging decision makers around the science of how climate change is already affecting wildlife, how that is expected to shift over time, and what actions or preparations can be taken now to help.

I couldn't resist reading Clark et al. 2023 right away despite my sad backlog. I once had a native plant garden guy tell me "at best non-native plants offer no value to pollinators and other wildlife, and most are harmful." Obviously false as an absolute! But how do they compare? Clark looked at 10 species in a Connecticut forest and found some invasive species (like honeysuckle) had more bugs (mass and protein) than the average for natives, but others (Japanese barberry) had fewer bugs. But birds seemed to forage both equally. It's a tiny study and I wish they hadn't pooled all native species, but I do like a study that counters "it depends!" to a truism in conservation.

Prichard et al. 2021
 is a review of several questions related to fire in US western forests (see Table 1 for the summary of questions & answers). They include whether and when/ how to use cutting trees and prescribed burns as tools for reducing wildfire risk and/or climate mitigation and/or ecological restoration. The authors argue that many dry forests (and some moist forests mixed into dry forest landscapes) historically experienced more frequent fires of low to moderate intensity (often set by Native Americans), but that these forests are now denser and more likely to have severe crown fires (especially as summers become warmer and drier). That in turn will cause some forests to be lost and shift to grasslands or other ecosystems. Read Table 1 for key takeaways, including that for many (not all) Western forests, thinning and prescribed burning are important tools. Side note: given the active debate on this topic, I asked for input from a few forest scientists deep in the lit, and they recommended this article.

Breznau et al. 2022
 has some scary news about science - not only is it less reproducible than we think, we can't even figure out why results vary so much. To be fair, they note that natural sciences and/or experimental research should have less variation than social science based on existing surveys (what this study looked at). But it's still concerning! Or preliminarily concerning but waiting for many more replicas, to take their message to heart. The models the 73 teams built were: 17% positive (more immigration increases support for social policies), 25% negative (more immigration reduces support for social policies), and 58% did not find a clear effect (the confidence interval included zero, although they may have had a positive or negative average effect). 61% of researchers concluded that immigration does not reduce support for social policies, 26% concluded it DOES reduce support (the text says 28.5% but it's a typo, reinforcing the core message of the paper), and 13% concluded it couldn't be tested w/ the given data. And Fig 2 shows that not only are results and conclusions all over the place, the variation isn't explained by the variables they tracked like expertise or prior beliefs. That means researcher bias is only part of the problem. I have some questions about the metanalysis itself that make me suspect they could have explained more of the variance with different methods (ironically, that is consistent with their core findings about how small method changes can drive results). But the paper reveals two problems: 1) scientists can produce different quantitative results from the same data and hypotheses, and 2) scientists' conclusions are often not well tied to their results (this paper found only ~1/3 of variation in conclusions came from how consistent the set of models each team used were). I see a lot of #2 when I peer review papers. Let's all remain humble and skeptical, and look for more replication in 2023!

Breznau, N., Rinke, E. M., Wuttke, A., Nguyen, H. H. V, Adem, M., Adriaans, J., Alvarez-Benjumea, A., Andersen, H. K., Auer, D., Azevedo, F., Bahnsen, O., Balzer, D., Bauer, G., Bauer, P. C., Baumann, M., Baute, S., Benoit, V., Bernauer, J., Berning, C., … Żółtak, T. (2022). Observing many researchers using the same data and hypothesis reveals a hidden universe of uncertainty. Proceedings of the National Academy of Sciences, 119(44), 1–8.

Chaplin-Kramer, R., Neugarten, R. A., Sharp, R. P., Collins, P. M., Polasky, S., Hole, D., Schuster, R., Strimas-Mackey, M., Mulligan, M., Brandon, C., Diaz, S., Fluet-Chouinard, E., Gorenflo, L. J., Johnson, J. A., Kennedy, C. M., Keys, P. W., Longley-Wood, K., McIntyre, P. B., Noon, M., … Watson, R. A. (2022). Mapping the planet’s critical natural assets. Nature Ecology & Evolution, 7(1), 51–61.

Cinner, J. E., Lau, J. D., Bauman, A. G., Feary, D. A., Januchowski-Hartley, F. A., Rojas, C. A., Barnes, M. L., Bergseth, B. J., Shum, E., Lahari, R., Ben, J., & Graham, N. A. J. (2019). Sixteen years of social and ecological dynamics reveal challenges and opportunities for adaptive management in sustaining the commons. Proceedings of the National Academy of Sciences, 116(52), 26474–26483.

Clark, R. E. (2023). Are native plants always better for wildlife than invasives? Insights from a community-level bird- exclusion experiment. Preprint available at

Dethier, E. N., Silman, M., Leiva, J. D., Alqahtani, S., Fernandez, L. E., Pauca, P., Çamalan, S., Tomhave, P., Magilligan, F. J., Renshaw, C. E., & Lutz, D. A. (2023). A global rise in alluvial mining increases sediment load in tropical rivers. Nature, 620(7975), 787–793.

Dickson, I., Butchart, S. H. M., Catalano, A., Gibbons, D., Jones, J. P. G., Lee‐Brooks, K., Oldfield, T., Noble, D., Paterson, S., Roy, S., Semelin, J., Tinsley‐Marshall, P., Trevelyan, R., Wauchope, H., Wicander, S., & Sutherland, W. J. (2023). Introducing a common taxonomy to support learning from failure in conservation. Conservation Biology, 37(1), 1–15.

Duncanson, L., Liang, M., Leitold, V., Armston, J., Krishna Moorthy, S. M., Dubayah, R., Costedoat, S., Enquist, B. J., Fatoyinbo, L., Goetz, S. J., Gonzalez-Roglich, M., Merow, C., Roehrdanz, P. R., Tabor, K., & Zvoleff, A. (2023). The effectiveness of global protected areas for climate change mitigation. Nature Communications, 14(1), 2908.

Grenz, J., & Armstrong, C. G. (2023). Pop-up restoration in colonial contexts: applying an indigenous food systems lens to ecological restoration. Frontiers in Sustainable Food Systems, 7(September), 1–12.

James, R., Fisher, J. R. B., Carlos-Grotjahn, C., Boylan, M. S., Dembereldash, B., Demissie, M. Z., Diaz De Villegas, C., Gibbs, B., Konia, R., Lyons, K., Possingham, H., Robinson, C. J., Tang, T., & Butt, N. (2023). Gender bias and inequity holds women back in their conservation careers. Frontiers in Environmental Science, 10(January), 1–16. or

Jewell, K., Peterson, M. N., Martin, M., Stevenson, K. T., Terando, A., & Teseneer, R. (2023). Conservation decision makers worry about relevancy and funding but not climate change. Wildlife Society Bulletin, November 2022, 1–14.

Knauer, J., Cuntz, M., Smith, B., Canadell, J. G., Medlyn, B. E., Bennett, A. C., Caldararu, S., & Haverd, V. (2023). Higher global gross primary productivity under future climate with more advanced representations of photosynthesis. Science Advances, 9(46), 24–28.

NatureServe. (2023). Biodiversity in Focus: United States Edition.

Prichard, S. J., Hessburg, P. F., Hagmann, R. K., Povak, N. A., Dobrowski, S. Z., Hurteau, M. D., Kane, V. R., Keane, R. E., Kobziar, L. N., Kolden, C. A., North, M., Parks, S. A., Safford, H. D., Stevens, J. T., Yocom, L. L., Churchill, D. J., Gray, R. W., Huffman, D. W., Lake, F. K., & Khatri‐Chhetri, P. (2021). Adapting western North American forests to climate change and wildfires: 10 common questions. Ecological Applications, 31(8).

Rubenstein, M. A., Weiskopf, S. R., Bertrand, R., Carter, S. L., Comte, L., Eaton, M. J., Johnson, C. G., Lenoir, J., Lynch, A. J., Miller, B. W., Morelli, T. L., Rodriguez, M. A., Terando, A., & Thompson, L. M. (2023). Climate change and the global redistribution of biodiversity: substantial variation in empirical support for expected range shifts. Environmental Evidence, 12(1), 7.

Toomey, A. H. (2023). Why facts don’t change minds: Insights from cognitive science for the improved communication of conservation research. Biological Conservation, 278(December 2022), 109886.

Walmsley, B. (2023). Satellite images show the widespread impact of mining on tropical rivers. Nature, 620(7975), 729–730.