White pines turn golden in the fall

By Richard B. Primack 

“… a pine tree is as substantial and as memorable a fact as a friend. I am more sure to come away from it cheered than from those who come nearest to being my friends.” Henry David Thoreau in his Journal. 

For most of the year, white pine trees (Pinus strobus) are covered with lustrous evergreen needles.  Pine needles typically last three summers, and about one third of the needles, the oldest ones, will turn golden brown each autumn before dropping off.  The process of leaf senescence takes a few weeks and is generally not that noticeable. 

In the autumn of 2021, white pine trees in Newton and elsewhere in the Boston area had a really different look. As a result of a severe summer drought in 2020, pine trees showed reduced growth 2021 and produced relatively few new needles. And some of the needles produced in 2020 may have undergone senescence in 2021. As a result, more than half of the needles on many pines trees turned color in 2021 in October, giving the trees a dramatic and unusual patchy reddish golden look.  

 

A. White pine tree in Newton in October 2021 covered with old needles.

B. The same tree a few weeks later in early November after wind has swept away the old leaves.

The effect was prolonged due to several weeks of calm weather that allowed the dead needles to linger. A windstorm in early November finally swept away the old needles, and the pine trees returned to their normal green coloring. Bare spaces on thin twigs showed where the old needles had been. 

A. A branch of the pine tree covered with old needles.

B. A branch after the old needles have been swept away by wind.

Climate Change in Urdu

By Richard B. Primack

“One studies books of science merely to learn the language of naturalists – to be able to communicate with them.” Henry David Thoreau in his  Journal. 

Voice of America recently broadcast an Urdu-dubbed interview with me  about the effects of climate change on autumn. The focus was on leaf color changes, and also included bird migration times and butterfly flight times.   This is a topic that our research group pioneered, led by the efforts of Amanda Gallinat.

Richard Primack is interviewed by Faiza Bukhari of Voice of America 

The focus of the interview is fall foliage 

The interview can be viewed here: link

Macrophenology: A new approach for investigating large-scale phenology patterns

Richard Primack

“The discoveries which we make abroad are special and particular – those which we make at home are general & significant. The further off the nearer the surface. The nearer home the deeper.”  Henry David Thoreau in his Journal. 

In a recent paper, we describe macrophenology as an exciting new field investigating large scale patterns of the timing of biological phenomena, such as flowering, leafing out, and bird migration. Macrophenology includes responses to a variety of drivers, including global climate change, across biomes, land‐use types, and species' ranges.

Figure 1. The timing of flowering, fruiting and leafing out in red maples in response to temperature can be examined over all of eastern North America using herbarium specimens.

Macrophenology can provide exciting and novel insights due to theoretical and applied advances and emerging tools, such as the availability of digitized museum specimens and remote sensing data.  Four key areas of macrophenology have special opportunities: (1) global drivers of phenology, (2) species range limits (3) interactions and mismatches among species, and (4) ecosystem processes. 

Figure 2.  Core concepts of macrophenology and their linkages.

Macrophenology can also investigate historical biogeography, phylogenetic patterns and geographic gaps in phenology research. 

Title: Macrophenology: insights into the broad‐scale patterns, drivers, and consequences of phenology. 

Published in American Journal of Botany journal. 

DOI: 10.1002/ajb2.1793

Noise in a Pandemic

By Alyssa Helmling 

Noise is inescapable in a large, bustling city like Boston, and it can be harmful to both wildlife and human health. The global COVID-19 pandemic altered the soundscape of cities as quarantine mandates led to dramatic decrease in human activity. We utilized this opportunity to study noise pollution before, during, and after the pandemic. 
 
With a student population over thirty-two thousand, the Boston University campus is typically a noisy place which we measured before the pandemic using the SPLnFFT sound meter app with iPhones. During the 2020 academic school year many students chose not to return to campus and instead took classes from home, and our new set of measurements showed that BU was now quieter. 

BU campus comes back to life as students return for an in-person school year. Photo by Cydney Scott (link).

And now that many pandemic-related restrictions had been lifted in Boston in 2021, high sound levels have returned in many areas of the BU campus. Our research demonstrates how much cities might be able to reduce harmful, pervasive noise.

Wildflower monitoring at botanical gardens

By Richard B. Primack

“To him who contemplates a trait of natural beauty no harm nor disappointment can come.” Henry David Thoreau in Natural History of Massachusetts. 

The phenology of wildflowers has been comparatively neglected in climate change research.  While researchers have extensively investigated the flowering times of wildflowers, there is surprisingly little information on their times of leaf out, leaf senescence, and fruiting. 

Primack monitors flowering times of marsh marigold.

In a recent article published in Functional Ecology, researchers describe the PhenObs initiative for making standard phenology observations on 199 wildflower species at four botanical gardens in Germany. The goal is to develop a protocol which could then be widely applied to wildflowers, and be used in both functional ecology and climate change research. 

Just a single date of flowering time needs to be recorded for bloodroot, rather than more detailed flowering stages.

Researchers recorded information on the dates of 14 stages of phenology involving leaf out, leaf senescence, flowering and fruiting. Analysis showed that these stages were highly correlated, so gathering such detailed information was not needed. The final recommendation is that for monitoring large numbers of species the dates of just five stages should be monitored: three stages of vegetative growth (initial growth, leaves unfolding, and leaf senescence), flowers open, and ripe fruits. 
 
This paper was published as:
Nordt, B.... R.B. Primack et al., 2020. The PhenObs initiative — A standardised protocol for monitoring phenological responses to climate change using herbaceous plant species in botanical gardens. Functional Ecology 35: 821-834. 

Link to Article 

Museum Collections Predict Species Abundance in The Wild

By Richard B Primack

 

“Most men can keep a horse or a certain fashionable style of living, but few indeed can keep up great expectations.” Henry David Thoreau in his Journal.  

 

Museum collections of plants and critters—small mammals, fish, insects, amphibians, trees, and wildflowers—are a good reflection of most species’ relative abundance in the wild. To reach this conclusion, a scientific team analyzed 1.4 million field observations and 73,000 museum records of over 22,00 species.

 

Species being monitored in the field.

 

Using this approach, museum records can potentially be used to identify species that are declining over time and may need extra protection to prevent them from going extinct. As the pace of environmental change accelerates due to climate change and urbanization, the analysis of museum records will provide unique insights into how natural communities are changing in response.

 

Museum specimens of plants can be assessed for their relative abundance.

 

One factor that needs to be considered is that species that are rare in the wild are consistently over-represented in museums, whereas common species are under-represented in museums, because collectors tend to favor rare and unusual specimens and to pass over individuals of common species.

 

The possibilities for this avenue of research will be enhanced by the millions of museum specimens currently being digitized and made available on-line. 

 

Title: Estimating Species Relative Abundances from Museum Records

Published in Methods in Ecology and Evolution journal, 

 

DOI: 10.1111/2041-210X.13705

 

URL:  https://besjournals.onlinelibrary.wiley.com/doi/abs/10.1111/2041-210X.13705

Pandemic lockdown highlights humans as both threats and custodians of biodiversity

 By Richard B. Primack

“There would be this advantage in travelling in your own country even in your own neighborhood, that you would be so thoroughly prepared to understand what you saw.” 

Henry David Thoreau in his Journal.

The global lockdown to mitigate COVID-19 pandemic health risks in 2020 altered human interactions with nature as described in a recent article. Hundreds of unusual species observations from around the world suggest that animals quickly responded to the reductions in human presence.

Figure 1: Wildlife reports from around the world describes changes in distribution and abundance during the pandemic.

Overall, there is a complex mixture of positive and negative effects of the pandemic lockdown on wildlife and nature conservation. 

Figure 2: The pandemic lockdown had a mixture of positive and negative effects on nature.

This unplanned global quasi-experimental perturbation highlights the dual role that humans play in threatening and protecting species and ecosystems. Pathways to favorably tilt this delicate balance toward protecting biodiversity include reducing human impacts and increasing conservation effectiveness. 

The article appeared as: Bates, AE, Primack, RB, et al. 2021. Biological Conservation. 

https://doi.org/10.1016/j.biocon.2021.109175 

Siberian plants shift phenology due to climate change

By Tara K. Miller

 
Siberia has undergone dramatic climatic changes due to global warming in recent decades. We used the Russian ‘Chronicles of Nature’ network to analyze the long-term (1976–2018) phenological shifts in leaf out, flowering, fruiting and leaf senescence of 67 common Siberian plant species. We found that plant phenology is changing dramatically in this remote and under-studied region.
 

Figure 1: Location of the study site by Lake Baikal, Siberia

 
Siberian boreal forest plants advanced their early season (leaf out and flowering) and mid-season (fruiting) phenology by 2.2, 0.7 and 1.6 days per decade, and delayed leaf senescence by 1.6 days per decade during this period.
 
Individual species shifted their phenology at different rates, and these results could be used to identify plants particularly at risk of decline due to their low adaptive capacity or a loss of synchronization with important ecological partners, such as pollinators or seed dispersers.
 

Figure 4: Species-specific phenological shifts of 67 Siberian plants from 1976 to 2018.
Dots indicate mean values, and horizontal lines are 95% confidence intervals.
(a) first leaf out, (b) first flower, (c) first fruit, and (d) leaf senescence.

 
 
This article appeared as: Rosbakh et al. 2021. Siberian plants shift their phenology in response to climate change. Global Change Biology. DOI: 10.1111/gcb.15744

Confronting ethical challenges in long-term research programs in the tropics

 By Richard B. Primack

“The deepest and most original thinker is the farthest traveled.” Henry David Thoreau in his Journal.

 

Ecologists and conservation biologists conducting long-term research programs in the tropics must confront serious ethical challenges. In a recent article, researchers share their experiences and perspectives.  Four key points are made:

 

The first and primary responsibility of anyone visiting and working in another country and culture is to understand cultural differences and adapt to them as much as possible. 

 

Local field assistants working with BU Professor Chery Knott (center) in West Kalimantan, Indonesia. (Photo © Tim Laman)

 

A second obligation is ensure that the research project brings added value to the local community, beyond simply paying for accommodation and support as would any other visitor (although that is important too!). 

 

Research Associate Poonam Rai discusses research project with community members outside Singalila National Park, in the Darjeeling Himalaya (India).  (Photo © Reinmar Seidler) 

 

A third responsibility among research programs is to share the resulting information and knowledge with local people, students, the scientific community, and government agencies. This often requires extra time and effort, yet it is imperative from both ethical and utilitarian viewpoints. 

 

Finally, researchers need to recognize that for the people who live in the midst of it, “biodiversity” is not always an unalloyed good. Researchers need to be empathetic concerns from the local community. 

 

This article appeared as:  Seidler et al. 2021.  Confronting ethical challenges in long-term research programs in the tropics. Biological Conservation https://doi.org/10.1016/j.biocon.2020.108933 

A Network of Tropical Forest Plots

By Richard B. Primack 

“In the summer we lay up a stock of experiences for the winter, as a squirrel of nuts. Something for conversation in winter evenings.” Henry David Thoreau in his Journal. 

Tropical forests are the most diverse and productive ecosystems on Earth. To investigate these forests, three networks of long-term forest plots have been established for South America (RAINFOR), Africa (AfriTRON) and Southeast Asia (T-FORCES). As described in a recent article, these initiatives are now integrated via ForestPlots.net cyber-infrastructure, linking colleagues from 54 countries across 24 plot networks. 

Tropical Forest plots in ForestPlots.net are widely distributed across the globe with the greatest abundance in South America. 

These networks are transforming our understanding of tropical forests and their role in the global environment. For example, there is no apparent relationship between tree species richness and carbon storage either within continents or across continents. 

There is no obvious relationship between species richness and carbon storage.

Also, tropical forests are responding to climate change by increasing their biomass; that is, they are acting as sinks for atmospheric carbon dioxide. 

Tropical forests are increasing in biomass, Asian forests (gray), increasing faster than South American (blue) and African (orange) forests.

This network of forest plots has the potential to utilize an old technology to gain important insights into the future of these diverse forests and their role in addressing global climate change. 

This article appeared as: ForestPlots.net et al. 2021. Taking the pulse of Earth’s tropical forests using networks of highly distributed plots. Biological Conservation https://doi.org/10.1016/j.biocon.2020.108849

July Rainstorms Change the Woods

By Richard B. Primack 

“To see wild life you must go forth at a wild season. When it rains & blows keeping men in-doors then the lover of nature must forth.” Henry David Thoreau in his Journal.
 
The heavy rains of the past two weeks have created unusual sights in the Webster Woods.  The outlet from Bare Pond is normally a gentle seasonal flow that is mostly below ground. However, during recent heavy thunderstorms, the stream became a surface torrent whipping the tannin-rich pond water into masses of foam. 
 

Foam stranded in the woods

 
 As the water receded, some of the foam was stranded in the woods.
 

A mass of foam looking like an octopus.

 
The foam sometimes took on animal-like shapes.
 

A sea-serpent of foam floats on a woodland pool.

 
 In other places the foam floated on quiet pools left behind by the flood.
 

Water spurts out from the ground.  

 
The rain was so intense that new springs started flowing.  In one place, water jetted out of the ground.

Biodiversity Science in China

By Richard B. Primack

“Almost all our improvements, so called, tend to convert the country into the town.”

 Henry David Thoreau in his Journal.

 

Over the past 35 years, China’s massive economic transformation has come at a significant cost to the environment, in terms of air and water pollution, habitat loss, and threats of species extinction  

 

China has also emerged as a leader in biodiversity conservation and research. This is important because China’s enormous human population depends on ecosystem services and because of its astonishing richness of species. 

 

A strong centralized funding and political structure in China allows national scale biodiversity projects to be organized more effectively than most other countries. For example, the Chinese Academy of Sciences organized 850 universities to assess the natural resources and biodiversity of China.  

 

Between 1980 and 2005, the number of national nature reserves (similar to national parks elsewhere) in China went from virtually none in 1980 to over 400 parks protecting close to 100 million hectares. China moved people out of these newly protected areas, and gave them economic alternatives.  

Figure 1. The area under protection in nature reserves and national nature reserves increased from 1980 to 2005, but has been stable or even declining since then (from Li and Pimm 2020).

While the capacity of China’s academic and research communjty to investigate and protect its astonishing biodiversity is increasing each year, the threats to biodiversity caused by China’s expanding economy is also increasing. Reconciling these two opposing trends is the crucial challenge faced by China’s expanding community of biodiversity scientists. 

 

To find out more, read these two references:

Primack, R. 2021.  Biodiversity science blossoms in China.  National Science Review, in press.  doi: 10.1093/nsr/nwab058 

Mi, Xiangcheng, Gang Feng, Yibo Hu, Jian Zhang, Lei Chen, R.T. Corlett, A.C. Hughes, S. Pimm, B. Schmid, Suhua Shi, J- Christian Svenning, & Keping Ma. 2021. The global significance of biodiversity science in China: an overview.  National Science Review  

doi: https://doi.org/10.1093/nsr/nwab032

Declining phenology observations in Japan

By Richard B. Primack 

“Do your work, and finish it. If you know how to begin, you will know when to end.”
Henry David Thoreau in Reform Papers.
 
The phenology observations being recorded by the Japanese Meteorological Agency (JMA) represent one of the most outstanding phenological data sets in the world and is certainly the best in East Asia. Since 1953, the JMA has been gathering data on over 100 phenological events (involving 34 plant species and 23 animal species) at 105 weather stations spanning Japan’s large latitudinal and climatic range. 
 

Monitoring of first flowering times of Japanese cherry trees (Prunus x yedoensis, Someiyoshino) in Tokyo will be continued.

Unfortunately, in November 2020 the JMA announced plans to dramatically reduce monitoring to just 6 plant phenology stages at 9 sites and eliminating animal observations altogether.   

First singing of bush warblers (Cettia diphone), which will be discontinued if the proposed cuts are implemented.

In a recent article, we describe a new approach to maintain the program, shifting the monitoring responsibility to citizen science organizations and other government departments. Some of the phenology observation sites could be moved to nearby parks and nature reserves.  
 
Doi, H., Higuchi, H., Kobori, H. et al. Declining phenology observations by the Japan Meteorological Agency. Nat Ecol Evol (2021). https://doi.org/10.1038/s41559-021-01459-3

Botanical gardens in climate change research

 By Richard B. Primack, Amanda Gallinat, Libby Ellwoood, and Abe Miller-Rushing 

“Do I not live in a garden – in paradise?  I can go out each morning before breakfast & do & and gather flowers, with which to perfume my chamber where I read & write all day.” 

- Henry David Thoreau in his Journal 

In a recent article published in the New Phytologist, we describe the vital and growing contribution of botanical gardens to climate change research, conservation, and public engagement. Botanical gardens host unique resources, including diverse collections of plant species growing in natural conditions and historical records. 

Amanda Gallinat recording fruiting times at the Arnold Arboretum

Researchers utilize networks of botanical garden networks to assess the phenological (timing) responses to climate change of hundreds of plants species. Associated studies include anatomical and physiological  characteristics. 

Launching a drone to monitor leaf out of trees at the Arnold Arboretum

New methods enhance the pace and impact of this research, including phylogenetic analyses that include evolutionary relatedness. Remotely controlled drones are used for monitoring the tree canopy.
 

Students recording phenology at the Chicago Botanic Garden

Botanical gardens have grown their citizen science programs, informing the public about climate change and monitoring plants more intensively than previously possible. 

Buzz about Newton Bees

By Richard B. Primack
 

“Possibly the day will come when the [landscape] will be partitioned off into so-called pleasure grounds, in which only a few will take a narrow and exclusive pleasure only.” 

- Henry David Thoreau in Excursions.

 
Honeybees and their hives inhabit many of Newton’s open spaces. The hives, which are licensed by the City, produce honey. Some beekeepers also place hives in classrooms allowing students to observe the hive through glass windows while bees forage outside via an external entrance.

Honeybee hive in Newton. 

 
The Newton Conservation Commission is discussing a new policy to ensure that beekeeping on conservation land conforms to best practices, including beekeepers having state licenses, registering hives, and annual state inspections for hives health.
 

Honeybees at hive entrance.

 
The commission is also deciding how many hives will be allowed per park due to their potential impacts on native bees, such as bumblebees and smaller solitary bees, and other pollinating insects, including butterflies.
 
Some members of Newton’s informal pollinator working group want the number of honeybee hives on conservation land reduced or even eliminated, arguing that domesticated honeybees, which are native to Europe, are not appropriate for conservation land.
 
A related concern is the danger to both native bees and honeybees presented by herbicides and pesticides which are widely applied to Newton’s lawns, golf courses and plantings. Should the use of these chemicals be more closely regulated and restricted?
 
This is shortened version of an article that appeared in the Newton Tab.

Managers drive biodiversity conservation success

By Richard B. Primack

“The outward obstacles which stood in my way were not living men but dead institutions.” 

- Henry David Thoreau in his Journal

While the success of a conservation project is usually determined by comparing different conditions, methods and techniques, the human component also plays surprisingly important role in the outcome of projects. In a recent editorial, we highlight how characteristics of project managers and conservation organizations affect the success of conservation projects and should be included in experimental design.

Figure 1.  Four stages in the restoration of river woodlands invaded by tamarisk
in the Western USA.  A. Tamarisk thicket with native cottonwoods in the background.
B. Bulldozer being used to remove tamarisk plants.  C. Team of scientists and
land managers evaluating a site after treatment.  D. Successfully restored site
with native cottonwood trees. 

We discuss an analysis of 243 restoration projects in the southwestern US. As expected, characteristics like temperature, precipitation, and site treatment were important in the successful recovery of the ecosystem.  However, the human variables explained an even larger percentage of the variability in outcomes.  For example, the more collaborators there were on a project, such as different government agencies, non-profits and scientists, the better the outcomes for plant recovery. In addition, contrary to expectations, the most educated managers had a lower rate of success than managers with less and more applied education. Further, projects of managers who focused on one project at a time rather than multiple jobs were the most successful. 

We argue that including the characteristics of managers and conservation organizations in experimental design could be an important step forward in improving the success of conservation and restoration projects.

Original publication: 
Primack et al. (2021) Manager characteristics drive conservation success. Biological Conservation. https://doi.org/10.1016/j.biocon.2021.109169  

COVID-19 Pandemic Causes Impacts and Opportunities for U.S. National Parks

By Abe Miller-Rushing

“What institutions of man can survive a morning experience?”

Henry David Thoreau in his Journal

 

In the early stages of the pandemic in April 2020, visitation to U.S. national parks declined by about 87 percent. In some parks visitation rebounded quickly as the summer progressed, while in others it remained low. For example, Denali National Park and Preserve in Alaska got less than 10 percent of its normal visitation in 2020. Other parks, particularly those near urban areas, experienced increased numbers of visitors as people sought safe areas for recreation and exercise.

Some park programs continued, though with masks and distancing.

Many long-term research projects and management actions at national parks were delayed or cancelled due to COVID 19, which complicates the challenge of collecting adequate data for analysis.

 

Researchers continued a project restoring mountain meadows
at Acadia National park, but many other projects were cancelled.

Parks and partner organizations hired fewer seasonal employees and cancelled many internship and volunteer programs, creating hardships for those who rely on these opportunities to gain experience and skills.

 

At the same time, many parks, such Yellowstone National Park in Wyoming and Montana, offered more online programs and content.

 

Researchers are now evaluating how these changes have affected wildlife protection, visitor services, education, and park management, and what lessons can be learned.

 

The paper was published in Biological Conservation: Abraham J. Miller-Rushing et al. 2021. COVID-19 pandemic impacts on conservation research, management, and public engagement in US national parks. Biological Conservation 257: 109038. https://doi.org/10.1016/j.biocon.2021.109038

Thoreau’s observations of fruiting times inform climate change research

By Tara K. Miller
 

“To replenish the possibility of mutual flourishing, for birds and berries and people, we need an economy that shares the gifts of the Earth, following the lead of our oldest teachers, the plants.”

- Robin Wall Kimmerer, The Serviceberry

 
In a recent Annals of Botany article, we compared Thoreau’s fruiting observations from the 1850s in Concord, MA with museum records from the past 150 years across New England to investigate the biological effects of climate change. We found a strong sequence of fruiting, with species such as blueberries fruiting in mid-summer and hollies fruiting later in autumn.   

Digitized museum specimens, such this bluebead lily,
were used to determine the time of fruit ripening.
© Consortium of Northeast Herbaria

 
This is the first use of Thoreau’s fruiting observations in scientific research, and builds on previous studies of Thoreau’s observations of flowering and bird arrival times. The present study was possible because pressed plant specimens – also known as herbarium specimens – have only recently been digitized in large numbers and made available on-line.

Lowbush blueberry plants were observed to fruit early in the year,
based on both Thoreau’s observations and museum specimens. © Jason S. 

 
Both Thoreau’s observations and museum specimens detect similar patterns of plant fruiting times, confirming that they can be combined to create larger and more powerful data sets for climate change and ecological research. However, the museum specimens, collected over a larger area and over more years than Thoreau, show an earlier start to fruiting and later ending than Thoreau’s Concord observations.

This deciduous holly, also known as winterberry, fruits later in the year. © SB Johnny 

Article: Comparing fruiting phenology across two historical datasets: Thoreau’s observations and herbarium specimens