Monday, May 15, 2017

Congratulations Dr. McDonough MacKenzie !

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.