Tuesday, August 8, 2017

Newton’s Lost Wetlands and Buried Brooks

Posted by Richard B. Primack


“As in many countries precious metals belong to the crown, so here natural objects of rare beauty should belong to the public.” -Thoreau in his Journal, 1861

Until about 120 years ago, Newton, MA, was filled with wet meadows, marshes, and swamps, connected by miles of brooks. Where did they go? In an article published June 7 in the Newton Tab, I explain how over the past two centuries, as Newton changed from farming to industry, and then to a Boston suburb, developers and town workers buried brooks in culverts or put them into channels. Wetlands were filled in and became the sites of playgrounds, schools, other public buildings, and residential neighborhoods. The forgotten brooks and wetlands of Newton are periodically remembered when basements, streets, and playgrounds become flooded after heavy rains. 


Modified 1892 drainage map showing the main brooks and associated wetlands, with the current position of some schools and village centers and the Newton Library. Map by Matt Rothendler.

Many New England towns are revisiting past decisions to bury and channelize brooks. Some towns are uncovering buried streams and removing the vertical walls of channels, allowing streams to re-integrate with wetlands. Restoring brooks to something closer to their original condition and adding natural vegetation could help clean the brook’s water, reduce flooding, provide natural water features, and improve the recreational value of playgrounds, parks, and neighborhoods. 


Cheesecake Brook appears wild and well-integrated with the surrounding forest along Fuller Street.

Returning brooks to their natural state is expensive in the short term, but in the long run the economic, environmental, and recreational benefits to the people and businesses of Newton might be worth it. After a long history of channelizing and burying brooks and filling in wetlands for development, Newton’s future could benefit from undoing some of its past. 

Cheesecake Brook is channelized and separated from natural habitat along Albemarle Road. 


Wednesday, August 2, 2017

Leaf Longevity at the Arnold Arboretum

Posted by Linnea Smith and Sarah Pardo

Hi! We are two new members of the Primack lab: Linnea Smith (yes, like Carolus Linnaeus), an undergraduate at Boston University who’s joined the Primack lab for the summer with funding from the BU UROP program; and Sarah Pardo, a rising senior at BU Academy.

Linnea and Professor Primack doing fieldwork at the Arnold Arboretum

We are investigating how many years evergreen plants at Harvard University’s Arnold Arboretum retain their leaves, and why. Ecological theory suggests that a leaf stays on the branch, photosynthesizing, until it’s made a profit on the energy that went into making it. We want to determine if the amount of time a leaf remains on a plant is more influenced by the original environment in which the plants grow, or their evolutionary history.


Professor Primack and Sarah examining pine needles in the field

When tree branches begin growing in the spring, a scar is formed on each twig where bud growth had halted the previous winter. By counting the number of scars, we can determine the number of years of twig growth and leaf formation on a tree branch. For example, say a twig has leaves on seven scar-separated segments and no leaves on the eighth segment or beyond. This tells us that leaves stay on that twig for seven years. So far we have evaluated 173 species including conifers such as pines, firs, spruces and hemlocks and other evergreens like rhododendrons and hollies.


Showing seven years of growth on tiger tail spruce at Arnold Arboretum

We’ve both really enjoyed our work in the Primack lab so far and appreciate the warm welcome we’ve been given!

Sunday, July 30, 2017

Old Plants, New Tricks: Phenological Research Using Herbarium Specimens

Posted by Amanda Gallinat

Herbarium specimens offer a unique opportunity to measure changes in plant phenology over broad time periods and geographic ranges. Many of the specimens currently housed in herbaria were collected in the 19th and 20th centuries, but in just the last decade there has been a huge increase in herbarium-based phenology research-- particularly addressing modern questions about how plants are responding to climate change.


Panchen et al., 2012 used herbarium specimens, combined with field notes and photographs, to show that 28 plant species in Pennsylvania are advancing their flowering over time.

Earlier this year, Richard Primack and I were co-authors on a review paper led by Charlie Willis entitled "Old Plants, New Tricks: Phenological Research Using Herbarium Specimens." The review, published in Trends in Ecology & Evolution, provides a thorough assessment of how herbarium specimens have already been used in phenology research, with most studies focusing on flowering, in northern, temperate biomes. 


Willis et al. (2017) Figure 1, shows where previously published herbarium-based phenology studies have been located (studies are indicated with blue circles; the larger the circle, the more species sampled). The heat map shows the source of digitized specimens (available via the iDigBio portal), which included 1.8 million specimens as of February 2017! 

We also discuss the future of herbarium specimens, with a special focus on the widespread digitization efforts currently underway. Digitized specimens are already being used by researchers to access more specimens in more locations than they could visit in person, and to use citizen science efforts to identify phenological stages online. Lastly, we review the biases inherent in using herbarium specimens, from those that arise during collection, to digitization, to observation. 


CrowdCurio is a web-based platform for identifying phenological stages on digitized specimens. In this case, citizen scientists could identify buds, flowers, and fruits on a lowbush blueberry specimen.

For our part, we plan to continue using herbarium specimens--including digitized specimens--to improve our understanding of species-specific effects of climate change, in both spring and autumn!

Thursday, July 20, 2017

Primack Lab in the News

Posted by Richard B. Primack

Here are a few recent pieces relating to Thoreau, climate change, and the Primack lab.




On July 12, Richard Primack was interviewed on National Public Radio for the program Morning Edition by Bob Oakes about research in Concord.



On June 28, Primack was interviewed on National Public Radio for the series Climate Change in Massachusetts by Carey Goldberg about the new program at the Cemetery using citizen scientists to monitor tree phenology. 




A picture of Primack taken by Sam Walker was a featured on the New York Times Learning Network. 510 people submitted comments on what Richard Primack was doing in the picture shown above. Most people thought he was mourning his dead wife. In fact he is recording the flowering time of bluets. The picture is staged as Primack always wears a hat in the field, and he never lies down when doing fieldwork, in part due to concerns about ticks.

Monday, July 10, 2017

Thoreau as a Scientist

Posted by Richard Primack

“Science is always brave, for to know, is to know good; doubt and danger quail before her eye.”
-Thoreau, in Excursions

Walden Pond has still many things to teach us about science and beauty

In the article Thoreau As Naturalist: A Conversation With Four Authors from the July-August issue of American Scientist, Dianne Timblin interviews four authors, including myself (author of Walden Warming: Climate Change Comes to Thoreau’s Woods), on the importance of Thoreau as a scientist and naturalist. The other authors are:

Richard Higgins, author of Thoreau and the Language of
 Trees

Geologist Robert M. Thorson, who recently wrote Thoreau, The Boatman

Laura Dassow
 Walls, author of the new book Henry 
David Thoreau: A Life

A key theme of the article is that Thoreau clearly wrote about the connections between science and larger social, political, and intellectual subjects. His views remain highly relevant to important issues facing modern society such as human health, sustainable development, environmental protection, and climate change.


Richard Primack and group of BU freshmen discuss the importance of Thoreau to climate change research

Saturday, June 17, 2017

Should you be using a professional editor?

Posted by Richard Primack

“Improve every opportunity to express yourself in writing as if it were your last.”
-Thoreau in his Journal, December 17, 1851

What are the secrets or best practices to achieving balance between work and family life? A recent news article in Nature, “Workplace habits: Full-time is full enough,” quotes several scientists describing their strategies. For many scientists achieving work-life balance means getting as much work done as possible in 40 hours per week, and devoting the rest of the time to family and personal life.

In the Nature article, I am quoted saying that I hire professional editors to help me work more efficiently in my position as a professor, textbook writer and editor. My comment inspired a post at the Dynamic Ecology blog, in which Meghan Duffy asks, “Have you ever used a professional editor for a proposal or manuscript?” In a follow-up article, I share my experiences in working with professional editors, and I summarize some key points here: Got a professional editor?


In this staged photo, Primack relaxes with the family dog, while a professional editor polishes a paper

I often hire professional editors on a freelance basis to help me write scientific papers, grant proposals, chapters of my conservation biology textbooks, professional correspondence, popular articles, press releases, and oral presentations. Hiring an editor often makes the difference between meeting or missing deadlines, or handing in sloppy work or well-written papers.

In my experience the best editors are advanced graduate students, post-docs, and early-career researchers working outside of tenure-track faculty positions. They are often excellent writers who want to make some extra money.

The amount of time needed by an editor depends on the document length, how much work the document needs, and the editor’s speed. Most recently, a professional editor spent 10 hours helping me on a grant proposal, 2 hours on an editorial for Biological Conservation, and 4 hours on a research article.

Working with editors can especially help scientists for whom writing is not a strength (including those for whom English is not their first language).

I think that working with a professional scientific editor can help many people in improving the chances of a grant being funded or a paper being accepted for publication.

Monday, June 12, 2017

My #DDIGstory

Posted by Caitlin McDonough MacKenzie

Recently the National Science Foundation announced that the Division of Environmental Biology will no longer accept Doctoral Dissertation Improvement Grant (DDIG) proposals, citing “increasing workload” and “changes in priorities.” DDIGs are relatively small grants (up to $13,000 in direct costs when I applied in 2014) with outsized impacts on the graduate student community: just read through the swell of #DDIGstory tweets that followed NSF’s announcement. 

My dissertation research was shaped and improved by a DDIG. The process of writing a DDIG proposal — developing the story around my hypotheses and research methods, creating a budget, working with the Research and Outreach office at Boston University —was a transformative experience. Applying for a DDIG introduced me to the inner workings of NSF proposals, revealing the process of navigating overhead and fringe benefits and planning a multi-year project. Just submitting my DDIG application felt like a major accomplishment, on par with passing qualifying exams. When I celebrated that fall, I did not realize that another notable life milestone would intersect with my DDIG.


Caitlin McDonough MacKenzie in the field at Acadia National Park

My DDIG memories are intertwined with my experience as a new parent. At my March 2015 committee meeting I announced two items of good news: I’m pregnant and my DDIG is funded! The DDIG provided my own source of support for two field seasons in Acadia National Park and allowed me to hire two wonderful undergraduate field assistants that April. Mentoring these students and teaching field methods was an invaluable experience, and though I was healthy and hiking all the way through the field season/second trimester, it was reassuring to know that my assistants were ready to pick up the slack if I needed a break. With DDIG funds, I traveled to the Ecological Society of America Annual Meeting that August to present a research talk. I was 34 weeks pregnant and my DDIG-supported conference-adjacent, air-conditioned hotel room was a perfect home base. 

The DDIG provided a kind of force field for me against the misogynist baggage that invariably strikes a pregnant grad student; it deflected questions about my commitment to a career in science or my ability to complete my dissertation. On a practical level, I had financial independence to do the fieldwork and present my research. But it was also a symbolic win, a sign that I was a serious scientist, regardless of the elastic waistband in my maternity field pants. Later, as I struggled through the haze of diapers, pediatrician appointments, sitz baths, and 3 am feedings, I could look forward to the second half of my DDIG fieldwork. The concrete plans built around my DDIG smoothed my transition from maternity leave: I returned to the field and accelerated through my last year of grad school. 

My DIGG is directly responsible for two chapters of my dissertation, two manuscripts currently ready for submission, and an unshakable confidence in my research and my ability to balance work and life, science and parenthood. I don’t think there is another fellowship or grant opportunity for ecology graduate students with the gravitas, the opportunity to engage in the full process of grant-writing, or the prestige of a DDIG. My career and my life would certainly not be the same without it. Eliminating this program is a serious error that the NSF should reconsider.

Monday, June 5, 2017

Humans vs. Drones and Satellites!

Posted by Richard Primack

“If there is nothing new on earth, there is still something new in the heavens.”
-Thoreau in his journal, Nov. 17, 1837

In an earlier post (April, 2016) we described comparing our on-the-ground observations of tree leaf-out times with data from LANDSAT satellites. Are data gathered by the two methods comparable, and can they be combined in climate change research?




We are now collaborating with Margaret Kosmala and David Basler from Harvard who are using drones to monitor tree leaf-out times at the Arnold Arboretum. Will drones flying a few hundred feet high provide similar dates of leaf-out to an observer on the ground and satellites in the sky? We will soon find out!


Science journalist Meera Subramanian recently wrote abut this project for Undark magazine.

Friday, May 26, 2017

What is the best way to detect changing bird populations?

Posted by Richard Primack
“We are made to exaggerate the importance of what work we do.”
-Thoreau in Walden

From 1969 until today, researchers at Manomet in southeastern Massachusetts have banded birds every autumn from August 15 to November 15, from Monday through Friday, from dawn to dusk. Many bird species have been declining in abundance and migrating later (or in a few cases earlier) over this 39-year period. 

American Redstarts have declined significantly in abundance at Manomet over the last 39 years (photo by Sam Roberts)

In a recent paper in Biological Conservation, we demonstrate that if bird banders sampled fewer days per week, even as few as two days per week, the patterns of changing abundance and timing are still detectable over the 39-year period. 

Significant declines in Red-eyed Vireo abundance are still detectable when sampling 2 days/week (photo by Sam Roberts)

Reducing the sampling to every other year does not affect the patterns, and most of the patterns are still detectable if birds are only captured every third or fourth year. 

Changes in the migration phenology of Blackpoll Warblers are still detectable when sampling every third year (photo by Sam Roberts)

When the data set is subsampled for shorter periods of time, however, such as 22, 15, and 11 years, most of patterns of changing abundance and timing are not detectable.

Our results demonstrate that the key to detecting long-term changes in abundance and timing of migration is to establish a simple and efficient sampling design that can be carried out over a long period of time.

You can read the full article here.

Monday, May 15, 2017

Congratulations Dr. McDonough MacKenzie!

Posted by Lucy Zipf

On May 2 our own Caitlin McDonough MacKenzie successfully defended her PhD thesis!


Caitlin is excited!

Her public talk titled "Climate change, species loss, and spring phenology in an around Acadia National Park, Maine" was well attended and received by members of the BU community, Caitlin's many collaborators both in Boston and Maine, and her loving family and friends.

Caitlin's work utilized historic data in conjunction with her own field observations and experiments to document changes in species abundance and phenology in Acadia and northern Maine, an understudied and iconic region.


Caitlin with one of her common gardens on Cadillac Mountain in Acadia National Park

She found that the phenology of plants and birds in and around Acadia are advancing with warming temperatures, but are doing so more slowly than in southern New England.

Further, using her field data on plant phenology along Acadia's three largest ridges and her common garden experiments Caitlin found that the temperature of local microclimate within a habitat is a better predictor of plant phenology than elevation, aspect, or plant source.

Caitlin will continue working in Acadia as a postdoc, having received a David H. Smith Conservation Research Fellowship from the Society for Conservation Biology.


Amanda, Caitlin, and Lucy on a Primack Lab outing this winter

We are so proud of all Caitlin has achieved at BU and look forward to her continued success!

Wednesday, May 10, 2017

Reading the Witness Tree

Posted by Caitlin McDonough MacKenzie


Lynda V. Mapes, a Bullard Fellow at the Harvard Forest, published an essay in the Boston Globe magazine last weekend. “What a year with a single tree reveals about climate change” is an intriguing narrative to the Primack lab, where we aim to coax entire communities of trees in Thoreau’s Concord and beyond to reveal the ecological effects of climate change from data spanning over one hundred and fifty years. I read Mapes as I was slogging through the final edits of my PhD defense talk, and I found in her writing a clear and compelling conversation about phenology. Inspired by her science communication, I dove back into my slides.

Mapes' essay on Caitlin's desk. Caitlin included a quote from this piece in the opening slides of her PhD defense talk

Mapes’ hyper-local focus — a single red oak tree in the Harvard Forest — provides a frame for presenting plant ecology research to the general public. From her tree, Mapes can call out the recent advances and varying methodological approaches in phenology studies. It’s a kind of meta-analysis for a popular audience: data from historic records (shout out to Thoreau), ground level-observations (John O’Keefe’s daily walks), phenocams (Andrew Richardson’s flux tower-mounted cameras), and remote sensing are drawn together and synthesized in this portrait of a red oak. As she climbs into the canopy of her oak, Mapes carries us with her: her writing provides perspective, and she deftly distills piles of scientific data into a vivid sweep of leaves. I've identified many red oaks in the field, but Mapes made me identify with hers.

The Boston Globe essay is adapted from Lynda V. Mapes' new book

As plant ecologists, it is not often that we get to see elements of our own work in popular culture or glossy magazine spreads. I’m not sure that I’ve ever seen the word ‘phenology’ in print outside of a scientific journal. Mapes easily folded this vocabulary into her essay, so that by the end of the article I forgot how startling it was to see ‘phenology’ in print in the Globe. I’m looking forward to repeating this revelation when I read her book WitnessTree: Seasons of Change With a Century-Old Oak.



Saturday, May 6, 2017

Primack featured on WGBH News!

Posted by Amanda Gallinat

This week, Richard Primack was featured on NPR's WGBH News!


In the program, Richard discusses finding Thoreau's field notes from the 1850's, replicating Thoreau's observations of leaf out and flowering in Concord today, and lessons learned about climate change. Rising spring temperatures are causing plants to leaf out and flower earlier today than in the 1850's, for some species by several weeks!

 Richard Primack recording leaf out at Walden Pond
photo credit: Craig Lemoult / WGBH News

The feature also draws connections between changing spring phenology and species loss. Concord has lost a quarter of its plant species since Thoreau's time, and another third are in decline. Richard notes "there are a lot of reasons why species have been lost from Concord, but at least part of the reason is climate change."

Richard Primack looking for spring leaves at Walden Pond 
photo credit: Craig Lemoult / WGBH News

WGBH journalist Craig Lemoult ends the segment with this reflection: "Like Thoreau, and like the rest of us, [Primack] feels joy in discovering a new bloom or leaves on a tree that was bare just days before. But for Primack, there’s also something troubling in the arrival of spring."

Monday, May 1, 2017

Yan Liu applies remote sensing to Acadia National Park

Posted by Richard B. Primack

For the past several years, Yan Liu, a University of Massachusetts Boston doctoral student working with Prof. Crystal Schaaf, has been collaborating with Caitlin McDonough MacKenzie to calibrate new remote sensing data of Acadia National Park to tree and shrub leaf out phenology on the ground.

Yan presented the results of her work at a PhD defense on March 21.



Yan’s work included comparisons of the leaf out times of trees across the entire Mt. Desert Island and among years.


A second aspect involved comparisons of leaf out times along transects with remote sensing images.

Tuesday, April 18, 2017

Special guests at Carleton College!

Posted by Amanda Gallinat

This spring, I am taking a quick detour from New England phenology to teach a Population Ecology course at Carleton College in Northfield, Minnesota. Last week was very exciting around here, because we had several special visitors: Pam Templer, Sam Roberts, and Dan and Erika Tallman!

On Monday (4/10) Pam Templer visited from Boston University to meet with students, tour the ecosystem ecology experiments in Carleton’s Cowling Arboretum, and to talk about her research as part of the weekly Biology Seminar Series. Pam gave a great seminar on the effects of winter climate change on N and C cycling, tree growth, and insect diversity in Northeast forests! Her talk was very well received, and students and faculty were all particularly interested in implications for the sugar maple industry.


Pam Templer with her Carleton host, Dan Hernandez

On Friday (4/14) Sam Roberts gave a talk to our Population Ecology class on his master’s research, using bird banding and nest searching data to measure demographic information of Saltmarsh and Seaside Sparrows in New Jersey, and using that information to model the population viability of those species over the next 50 years. He included many great photos and videos of his field methods.

A video Sam Roberts took in the salt marsh, showing the difficulty of finding nests!

Sam and the Pop Eco students talked through potential management strategies, like predator management programs, and he showed some examples of how to incorporate management scenarios into population models. This was a great application of the population growth models we've been using in class.

Later that afternoon, the students got to see bird banding in action! Dan and Erika Tallman visited the Cowling Arboretum to demonstrate and discuss the bird banding process.


Dan Tallman bands a chickadee captured behind the Arboretum offices

In an hour and a half, we caught 16 Black-capped Chickadees, 3 Dark-eyed Juncos, 1 Downy Woodpecker, 3 House Finches, and 1 Red-bellied Woodpecker. The students learned about ageing and sexing birds, and even got to release them!

A Carleton student releases a chickadee!

Primack Alums at the Smith Fellowship Spring Retreat

Posted by Caitlin McDonough MacKenzie

Last week I traveled to Oregon’s Mt Hood for my first Smith Fellowship Retreat. Smith Post-Doctoral Fellows come together for three weeks each year from across the country to meet each other and participate in professional development workshops.

Abe Miller-Rushing, from Acadia National Park, and Jacquelyn Gill from University of Maine, who will be my mentors for the next two years, joined me in Oregon. We talked about the logistics of getting equipment into remote subalpine lakes, opportunities for public outreach, and scheduling for the summer.


Abe and Caitlin at Mirror Lake below Mt Hood. 

The retreat was a wonderful opportunity to connect with other fellows and their mentors in other disciplines of conservation, and to recharge by the fire at Timberline Lodge. We also snow-shoed to Mirror Lake, ate delicious cookies, and drank Oregon beers. The schedule was both energizing and relaxing. I’m looking forward to my Smith Fellowship working with Abe and Jacquelyn to study paleo-vegetation dynamics above treeline in Maine!

Wednesday, April 5, 2017

Cherry flowers in danger of frost and insects

Posted by Richard B. Primack

Cherry trees in flower are one of the most beautiful sights of spring. In Japan, Korea, Washington, D.C., and many other places, the cherry blossom season is a time for festivals and merriment.

A warming climate is causing cherry trees to flower several weeks earlier in the spring, shifting the dates of the festivals as well. However, with an earlier flowering comes an increased risk of flowers being damaged by late season frosts, and a greatly diminished floral display. Also, a mild winter can result in outbreaks of insects that can further damage the flowers and young leaves. As a consequence, climate change has the potential to drastically decrease the abundance of cherry blossoms.

In 2015, there was a spectacular display of cherry blossoms at the Arnold Arboretum, as shown by this Sargent’s cherry tree, and a close-up of a flowering branch:




In 2016, by contrast, there was a warm late winter and early spring, stimulating an early flowering of cherry trees. Unfortunately, a late frost combined with an outbreak of gypsy moth caterpillars severely damaged the flowers, as shown by these photos of the same Sargent’s cherry tree:



An article on this topic, which extensively quotes Richard Primack, appeared in the German on-line magazine Deutsche Welle.

Wednesday, March 29, 2017

Leaf Emergence and Fall (LEaF): A Pardee Center Initiative

Posted by Richard B. Primack and Amanda Gallinat

“All change is a miracle to contemplate; but it is a miracle which is taking place every instant.” 
-Thoreau in Walden

In the autumn of 2016, the three-year project known as Leaf Emergence and Fall (LEaF) was initiated with funding from Boston University's Pardee Center for the Study of the Longer-Range Future. The goal of LEaF is to organize workshops for New England scientists who are studying the impacts of climate change on spring and autumn leaf phenology. Understanding how climate change affects the timing of the start and end of the growing season has implications for forestry, the uptake of carbon dioxide from the atmosphere, the movement of water into streams, the water table and the atmosphere, land use policy, and the ecology of many animals.

Alyssa Rosemartin (USA National Phenology Network) and Lucy Zipf (BU) talking at the recent LEaF meeting on March 17th

LEaF workshops provide opportunities for researchers, especially graduate students and post-doctoral researchers, to exchange ideas and develop new collaborations. The most recent LEaF meeting was held at the Pardee Center on March 17th. A total of 18 people attended, including researchers from Harvard University, the University of Massachusetts at Boston, the National Phenology Network, and Boston University. People were clearly excited to meet each other and exchange ideas, and many people began to develop ideas for new collaborative projects!

Pamela Templer (BU Biology) exchanges ideas with Eli Melaas (BU Earth & Environment)