Showing posts with label migration. Show all posts
Showing posts with label migration. Show all posts

Wednesday, May 1, 2024

May 2024 science summary

Blackwater River trail

Ahoy,

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 http://bit.ly/sciencejon (no need to email me).

CONSERVATION IMPACT:
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?


WETLANDS:
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.


MIGRATORY SPECIES:
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: https://www.unep.org/news-and-stories/press-release/landmark-un-report-worlds-migratory-species-animals-are-decline-and


BIODIVERSITY:
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.

REFERENCES:

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. https://www.fws.gov/project/2019-wetlands-status-and-trends-report

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. https://doi.org/10.1126/science.adj6598

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. https://doi.org/10.1073/pnas.2314231121

UNEP-WCMC, 2024. State of the World’s Migratory Species. UNEP-WCMC, Cambridge, United Kingdom.
https://www.cms.int/en/publication/state-worlds-migratory-species-report

Sincerely,
 
Jon

 
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, February 3, 2020

February 2020 science journal article summary

Ice crystals on windshield

Greetings,

This month is a mix of topics; some papers came out recently that were too cool for me to wait to review with other similar ones, and I couldn't resist plugging the latest paper I worked on (Hamel et al. 2020). If you know someone who wants to sign up to receive these summaries, they can do so at http://bit.ly/sciencejon

Also, a 12-minute video came out recently about the 2017 March for Science, and I show up in it a few times. It's called "SciComm: Raising Our Voice for Science and Public Policy," it's directed & produced by Larry Kirkman (larry@american.edu) and Shannon Shikles at the Center for Environmental Filmmaking at American University, and you can watch it here: https://vimeo.com/383209723


CLIMATE CHANGE:
Sippel et al. 2020 bucks the pattern where climatologists emphasize how distinct climate and weather are. Past research has shown the impact of climate change on certain weather events, but this paper actually detects the impact of climate change on any given day since late March 2012! By summarizing weather data all over the world, they found that we’ve been clearly outside of natural variability for the past 8 years on a daily basis. On a monthly basis, climate change has been detectable from global weather data since 2001. You can read a newspaper article about the paper at https://www.washingtonpost.com/weather/2020/01/02/signal-human-caused-climate-change-has-emerged-every-day-weather-study-finds/  I love the description of this paper from meteorologist Maria LaRosa: “[it’s] like looking closely at an impressionist painting –  you can't say what the picture is until you step back and look at the whole”


ECOSYSTEM SERVICES:
Chaplin-Kramer et al. 2019 produced global maps summarizing ecosystem services (sort of) for coastal protection, water quality regulation, and crop pollination, now and in 2050 (under three different scenarios). One twist is that they go beyond the usual definition of ecosystem services (benefits provided by nature and received by people who need them) to also look at the 'benefit gap' where there are people with needs nature is not currently meeting (see Fig 2, bottom row, pink / lavender color). There's a lot to explore here, but one finding is that both SE Asia and Africa are expected to have increasing gaps for all three services. There's plenty of uncertainty, but this is a great set of data to think about trade-offs under different future paths. You can explore their results in a web map at http://viz.naturalcapitalproject.org/ipbes/

Johnson et al. 2019 analyzed where it makes economic sense to protect undeveloped land within 100-year floodplains across the U.S. They compared  expected flood damages (over the next 30-50 years) to land acquisition cost (to prevent development and avoid damages). They found benefits exceeded acquisition cost for about 1/3 of unprotected natural areas, and that the strongest benefits were within the 20-year floodplain but outside of the 5-year floodplain. Compared to the 5-year floodplain, these areas are more likely to get developed even though they flood less often, leading to more potential damages. Figure 3 has a map of the counties with the highest benefit:cost ratio, focused in Appalalachia, Arizona, and a mix of other places. Note that buying undeveloped lands avoids the controversy associated with asking or forcing people already living within floodplains to move.

Brancalion et al. 2019 looks at opportunities to restore lowland tropical rainforests around the world. They evaluate both the benefits (including biodiversity, climate mitigation & adaptation, and water security) and feasibility (land opportunity cost, ecological uncertainty, and chance of forest persistence). Figure 2 shows where there's the most opportunity, both by area (Brazil) and by combined benefit and feasibility (Madagascar, Tropical Andes). Where to focus depends on your goal - the places with the most total benefits are generally less feasible (higher land costs and competition, e.g. areas where habitat loss is recent and ongoing). But Figure 3 shows several examples of countries with restoration commitments who appear to have large areas with relatively high benefits and feasibility.


LANDSCAPE ECOLOGY:
Fahrig 2017 & Fahrig et al. 2019 are challenging but important reviews on the ecological impact of habitat fragmentation at the landscape scale (big areas). Their key findings are that with the amount of habitat loss being equal, fragmentation per se typically (70% of the time) didn't significantly impact biodiversity or ecological function at all. Even stranger, when it did have a significant impact, 3/4 of the time it was positive (even for threatened and rare species)! Section 5 in the 2017 paper summarizes the different explanations that authors of the primary studies provided, from fragmentation boosting functional connectivity (by reducing distance between patches) to edge effects and others. She concludes that in most cases we confound habitat loss with fragmentation, and that most of the time our intuition (that fragmentation per se is bad) is incorrect. She also notes that authors sometimes bury or caveat their findings of positive effects of fragmentation, which is one reason her findings continue to seem so wrong. My key take-aways are: 1) it's very hard (but very important) to examine our biases and deeply held beliefs when reading contrary science, 2) there is a good case made in the 2019 paper that small patches are under-protected, given their importance in many landscapes.

Jones et al. 2019 used GPS collars to track both migratory and resident pronghorn, and to model what features they avoided and which they ignored. They found that pronghorn were very reluctant to cross fences (consistent with under studies - they tend to crawl under rather than jump over), and avoided roads, but mostly ignored oil and gas well pads. There's a lot of other findings in their model, but the one I found most interesting was the concern that if ranches add more fencing to allow rotational grazing, it could have serious negative impacts on pronghorn and  mule deer unless wildlife-friendly fences are used.


RESEARCH IMPACT:
Hamel et al. looks at how scientific information was perceived and used in decision making for a water fund in Brazil. Through interviews, we determined that the hydrological modeling and monitoring data was NOT used in designing and implementing the water fund. But counter-intuitively, having done the analysis using complex models and high-resolution data was seen as important for the water fund to be seen as scientifically credible. So ironically, even though the credible models were not actually used, their existence helped build support for the overall water fund. Despite this, as long as monitoring data was used to calibrate and validate the model, a simpler model (InVEST, as opposed to SWAT) and coarser data resolution (30m, as opposed to 1m) would have met the information needs of the users. We should have had more frank discussions up front with the ultimate users of the information to produce a model seen as credible and actually used, while avoiding over-investment in model complexity that wasn't needed.

Samanta et al. 2019 is a paper about a program in Michigan to improve water quality issues from agriculture via a really well thought out collaboration (w/ scientists, practitioners, universities, farmers, and industry). Lack of public funding has pushed many farmers to rely on private crop advisors, who don't always share conservation opportunities (like cover crops, reduced tillage, and nutrient management) with farmers (especially as tied to programs involving lots of paperwork). They found it was critical to improve active communication & trust at all levels (especially about funding available).  Conservation was constrained by funding, and potentially by the shift of crop advisors to often be less comprehensive and represent a single company. The authors emphasize the need to integrate social science like this from the very beginning of projects.


REFERENCES:
Brancalion, P. H. S., Niamir, A., Broadbent, E., Crouzeilles, R., Barros, F. S. M., Almeyda Zambrano, A. M., … Chazdon, R. L. (2019). Global restoration opportunities in tropical rainforest landscapes. Science Advances, 5(7), eaav3223. https://doi.org/10.1126/sciadv.aav3223

Chaplin-Kramer, R., Sharp, R. P., Weil, C., Bennett, E. M., Pascual, U., Arkema, K. K., … Daily, G. C. (2019). Global modeling of nature’s contributions to people. Science, 366(6462), 255–258. https://doi.org/10.1126/SCIENCE.AAW3372

Fahrig, L. (2017). Ecological Responses to Habitat Fragmentation Per Se. Annual Review of Ecology, Evolution, and Systematics, 48(1), annurev-ecolsys-110316-022612. https://doi.org/10.1146/annurev-ecolsys-110316-022612

Fahrig, L., Arroyo-Rodríguez, V., Bennett, J. R., Boucher-Lalonde, V., Cazetta, E., Currie, D. J., … Watling, J. I. (2019). Is habitat fragmentation bad for biodiversity? Biological Conservation, 230(October 2018), 179–186. https://doi.org/10.1016/j.biocon.2018.12.026

Hamel, P., Bremer, L. L., Ponette-González, A. G., Acosta, E., Fisher, J. R. B., Steele, B., … Brauman, K. A. (2020). The value of hydrologic information for watershed management programs: The case of Camboriú, Brazil. Science of The Total Environment, 135871. https://doi.org/10.1016/j.scitotenv.2019.135871

Johnson, K. A., Wing, O. E. J., Bates, P. D., Fargione, J., Kroeger, T., Larson, W. D., … Smith, A. M. (2019). A benefit–cost analysis of floodplain land acquisition for US flood damage reduction. Nature Sustainability. https://doi.org/10.1038/s41893-019-0437-5

Jones, P. F., Jakes, A. F., Telander, A. C., Sawyer, H., Martin, B. H., & Hebblewhite, M. (2019). Fences reduce habitat for a partially migratory ungulate in the Northern Sagebrush Steppe. Ecosphere, 10(7). https://doi.org/10.1002/ecs2.2782

Samanta, A., Eanes, F. R., Wickerham, B., Fales, M., Bulla, B. R., & Prokopy, L. S. (2019). Communication, Partnerships, and the Role of Social Science: Conservation Delivery in a Brave New World. Society & Natural Resources, 0(0), 1–13. https://doi.org/10.1080/08941920.2019.1695990

Sippel, S., Meinshausen, N., Fischer, E. M., Székely, E., & Knutti, R. (2020). Climate change now detectable from any single day of weather at global scale. Nature Climate Change, 10(1), 35–41. https://doi.org/10.1038/s41558-019-0666-7

Sincerely,

Jon

p.s. If you'd like to keep track of what I write as well as what I read, I always link to both my informal blog posts and my formal publications (plus these summaries) at http://sciencejon.blogspot.com/

Monday, November 4, 2019

November 2019 Science Journal Article Summary

Spider at Bodie lighthouse
Happy (belated) Halloween!

This month I'm focused on landscape ecology and climate change (yet again), and unfortunately not spiders or other spooky topics. I also have a webinar on research impact to plug, and a new paper out on the adoption of new practices. As always people can sign up for this newsletter at http://bit.ly/sciencejon

Are you a scientist who produces research that you want to have real-world impact? If so, I'll be hosting a session on December 3 (1p EST) with a series of recommendations from a paper that I have in review. You can learn more and register here: https://zoom.us/webinar/register/WN_Q78ubqH9TL6tkmLQCRyAsw and can read the draft paper at http://bit.ly/strongerscience


ORGANIZATIONAL LEARNING / BEHAVIOR CHANGE:
Reddy et al. 2019 (I'm a co-author) looked at the adoption of a new conservation planning framework (Conservation by Design 2.0) being rolled out by The Nature Conservancy. Some staff & teams were early adopters, but it was slow to spread. But people who worked on projects with early adopters from different teams were more likely to use the new practices. Having early adopters work with people from different teams who are slower to change can speed exposure to new ideas and help everyone to learn and adapt. Supervisors should encourage talent-sharing and learning exchanges so this happens more.


LANDSCAPE ECOLOGY:
Sawyer et al. 2019 looks at how which route animals take during migration impacts their survival. Their key finding was that both their choice of destination ("summer range") and how to get there had a big impact on survival. They found 'exterior' routes (near the edge of the migration corridor) had 30% lower survival compared to interior routes. However - look close at Figure 3 (red means high mortality risk, green low, blue medium). It appears to me that their finding may be an artifact of the fact that mortality is driven by specific destinations, and they didn't report this b/c of how they aggregated summer range boundaries. So it's unclear whether the risk comes from where they go or how they get there.

Tucker et al. 2018 uses GPS data from ~800 animals from 57 mammal species around the world (see Fig 1 for locations) to assess how animals move differently depending on how much humans have modified the landscape (e.g. through buildings, farms, lights, transit, etc.). Unsurprisingly they found more modified areas resulted in significantly less animal movement - especially over time periods of a day or more. They also compared species and confirmed that predators and larger animals tended to move farther, as did animals in resource-poor areas. No big shocks here, but an interesting read.

Tambosi et al. 2014 presents a method to identify priority areas that are highly likely to improve the ecological resilience of a landscape. They look for areas with intermediate resilience - meaning they have decent amounts of habitat and connectivity already, and through targeted restoration they could better connect more intact areas. They then apply this method to the Atlantic Forest in Brazil to identify ~15 million ha of priority areas to reforest (they don't report which subset of that is high vs low priority). It's a relatively simply graph theory approach to connectivity.


CLIMATE CHANGE:
Betts 2000 has a point that should be better known. He found boreal forests' ability to mitigate climate change is weak (and may even be negative). Dark needles (present year round) absorb a lot more infrared radiation than typically snow-covered ground. This reduction in albedo (diffuse reflectivity) reduces and in some cases outweighs the carbon sequestration. He compared forest to cropland, but didn't account for N2O emissions from fertilizer.

Li et al. 2015 compares the net impact of different kinds of forests on local weather, considering albedo and evapotranspiration. Their key finding is that "tropical forests have a strong cooling effect throughout the year; temperate forests show moderate cooling in summer and moderate warming in winter with net cooling annually; and boreal forests have strong warming in winter and moderate cooling in summer with net warming annually." This means that the net climatic effect (accounting for carbon sequestration as well as local weather) of tropical forests (and to a lesser extent, temperate forests) is stronger than indicated by carbon alone, while for boreal forests the carbon benefit is significantly offset.

Minx et al. 2018 is an overview from a 3-part series on negative emissions (which they define as reforestation, soil carbon, biochar, BECCS, DACCS, enhanced weathering & ocean alkalinization, and ocean fertilization). Table 2 summarizes potential impact and costs from various studies, and Fig 6 has a great visual synthesis of these data. They find afforestation, reforestation, and soil carbon as ready for large-scale deployment (albeit reversible), and all but ocean fertilization as having potential to deliver benefits by 2050. There are lots of other good insights here and it's worth reading.

Fuss et al. 2018 is a look at costs, potential, & side effects from a 3-part series on negative emissions (which they define as reforestation & afforestation, soil carbon, biochar, BECCS, DACCS, enhanced weathering & ocean alkalinization, and ocean fertilization). It has good details for each negative emissions option, but the most useful part for me was Figure 2, which shows the relative contribution needed from 'conventional abatement' (e.g. reducing fossil fuel emissions via clean energy & efficiency, and reducing land use change) vs 'negative emissions' over time.


REFERENCES:
Betts RA. 2000. Offset of the potential carbon sink from boreal forestation by decreases in surface albedo. Nature 408: 187–190.

Fuss S, Lamb WF, Callaghan MW, Hilaire J, Creutzig F, Amann T, Beringer T, Garcia W de O, Hartmann J, Khanna T, Luderer G, Nemet GF, Rogelj J, Smith P, Vicente JLV, Wilcox J, Dominguez M del MZ, Minx JC. 2018. Negative emissions — Part 2 : Costs , potentials and side effects. Environmental Research Letters 13: 063002.

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.

Minx JC, Lamb WF, Callaghan MW, Fuss S, Hilaire J, Creutzig F, Amann T, Beringer T, De Oliveira Garcia W, Hartmann J, Khanna T, Lenzi D, Luderer G, Nemet GF, Rogelj J, Smith P, Vicente Vicente JL, Wilcox J, Del Mar Zamora Dominguez M. 2018. Negative emissions - Part 1: Research landscape and synthesis. Environmental Research Letters 13

Reddy SMW, Torphy K, Liu Y, Chen T, Masuda YJ, Fisher JRB, Galey S, Burford K, Frank KA, Montambault JR. 2019. How different forms of social capital created through project team assignments influence employee adoption of sustainability practices. Organization & Environment .

Sawyer H, LeBeau CW, McDonald TL, Xu W, Middleton AD. 2019. All routes are not created equal: An ungulate’s choice of migration route can influence its survival. Journal of Applied Ecology 1–10.

Tambosi LR, Martensen AC, Ribeiro MC, Metzger JP. 2014. A framework to optimize biodiversity restoration efforts based on habitat amount and landscape connectivity. Restoration Ecology 22: 169–177.

Tucker MA, Böhning-Gaese K, Fagan WF, Fryxell JM, Van Moorter B, Alberts SC, Ali AH, Allen AM, Attias N, Avgar T, Bartlam-Brooks H, Bayarbaatar B, Belant JL, Bertassoni A, Beyer D, Bidner L, van Beest FM, Blake S, Blaum N, Bracis C, Brown D, de Bruyn PJN, Cagnacci F, Calabrese JM, Camilo-Alves C, Chamaillé-Jammes S, Chiaradia A, Davidson SC, Dennis T, DeStefano S, Diefenbach D, Douglas-Hamilton I, Fennessy J, Fichtel C, Fiedler W, Fischer C, Fischhoff I, Fleming CH, Ford AT, Fritz SA, Gehr B, Goheen JR, Gurarie E, Hebblewhite M, Heurich M, Hewison AJM, Hof C, Hurme E, Isbell LA, Janssen R, Jeltsch F, Kaczensky P, Kane A, Kappeler PM, Kauffman M, Kays R, Kimuyu D, Koch F, Kranstauber B, LaPoint S, Leimgruber P, Linnell JDC, López-López P, Markham AC, Mattisson J, Medici EP, Mellone U, Merrill E, de Miranda Mourão G, Morato RG, Morellet N, Morrison TA, Díaz-Muñoz SL, Mysterud A, Nandintsetseg D, Nathan R, Niamir A, Odden J, O’Hara RB, Oliveira-Santos LGR, Olson KA, Patterson BD, Cunha de Paula R, Pedrotti L, Reineking B, Rimmler M, Rogers TL, Rolandsen CM, Rosenberry CS, Rubenstein DI, Safi K, Saïd S, Sapir N, Sawyer H, Schmidt NM, Selva N, Sergiel A, Shiilegdamba E, Silva JP, Singh N, Solberg EJ, Spiegel O, Strand O, Sundaresan S, Ullmann W, Voigt U, Wall J, Wattles D, Wikelski M, Wilmers CC, Wilson JW, Wittemyer G, Zięba F, Zwijacz-Kozica T, Mueller T. 2018. Moving in the Anthropocene: Global reductions in terrestrial mammalian movements. Science 359: 466–469.


Sincerely,

Jon