Knee high in the waters of California

June 9, 2022

Unlike last year, now known as California's mega drought, this year has started with water in the ponds. Ty McCaffrey is leading the team this year after successfully defending his thesis (Congrats Ty). They are about a month into sampling with some notable details already. For the first time in...


Summer necropsy well underway

June 9, 2022

The summer necropsy team has been busy dissecting and identifying parasites. This summer we have six new necropsy technicians (Carmella Bonato, Skylar Davidson, Erin Hobday, Hannah Garner, Jasmine Groves, and Clara Hassan). All of the new members are fully supported by the awards they earned! Specifically, NSF RAHSS (Clara), UROP...

jamie cut

Osprey's at the Denver Nature and Science Museum

June 7, 2022

Laboratory Manager Dana Calhoun MS, LVT, and Research Technician, Jamie Curtis, were invited to the Denver Nature and Science Museum to dissect P. Haliaetus commonly known as osprey. Rough dissections were made at the facility to remove the gastrointestinal tracts of five ospreys. Back in the lab, Dana has been...

field frog

Accepting undergraduate PAID research experience

Jan. 11, 2022

The Johnson Laboratory ( http:/// ) here at the University of Colorado is actively seeking CU Boulder undergraduate students to gain research experience and get PAID ($2,000-3,000) this summer. We are looking for independent, self-motivated undergraduate students who are passionate about pursuing research in aquatic ecology and conservation to apply...

thumb cheato

New Paper! Worm-eat-worm world

Oct. 15, 2021

Graduate student Brendan Hobart lead an investigation into the association of a snail predator Chaetogaster limnaei and nine trematodes...

snail art 2

Science intersects with visual arts

Sept. 24, 2021

Undergraduate student Madelyn Maclaughlin drew a visual representation of her group project in this years annual UROP Sidewalk Symposium...

Wynne Piet Tavis

Congrats to Wynne and Travis!

Sept. 9, 2021

Both graduate students Wynne Moss and Travis McDevitt-Galles successfully completed their PhD’s and landed competitive post-doctoral positions.....

Oliva bullfrog

What is the relationship between Bd and bullfrogs?

Sept. 3, 2021

Olivia Milloway, one of our NSF REU recipients for this summer, explored our 10-years of field collection data from the Bay Area of CA to investigate the relationship between Bd transmission and bullfrogs......

Johnson lab

Join us! Accepting graduate applications

Aug. 25, 2021

We are currently accepting applications for highly motivated, dynamic, and engaged candidates interested in pursuing a Ph.D. in aquatic disease ecology.....

thumnail field

That's a wrap!

Aug. 25, 2021

Field season for 2021 is offically over! This year the CA mega-drought was raging. In fact 45 ponds went dry in total, nearly half of our sites! Interestingly, 37 of those were dry before our second visit which typically occurs in July. We are exicted to investigate how amphibians parasites...

alpine lake, zooplankton, ice-off, Kelly Loria

New Paper! Life on Top of The World

Nov. 11, 2020

In a new paper from Journal of Plankton Research , Kelly Loria, Kyle Christianson, and Pieter Johnson use a decade of data from an alpine lake in Colorado to understand how shifting climate is altering the zooplankton community. Phenology of alpine zooplankton populations and the importance of lake ice-out Abstract...

Brevoortia tyrannus, parasitic isopod, Olencira praegustator, Atlantic menhaden

New Paper! Invasion of the Isopods

Nov. 11, 2020

Former undergraduate student Dylan Rose teamed up with Dr. Johnson and Dana Calhoun to conduct a study on Olencira praegustator, an isopod that parasitizes the mouths and gill chambers of Brevoortia tyrannus (Atlantic menhaden), a key economic species that supports the largest fishery on the eastern U.S. coast. Infection prevalence...

Ribeiroia ondatrae, pacific chorus frog, pacific tree frog, Pseudacris regilla, malformation

New Paper! Disease's Hidden Death Toll

Nov. 11, 2020

Understanding how many animals are killed by wildlife disease is a tremendously difficult question to address. In a new study, Mark Wilber and colleagues combine information on parasite distributions, extensive field data, and laboratory experiments to estimate – for the first time – how many amphibians die annually from trematode...

California wetlands, Johnson Lab, Research, Amphibians

Welcome Home, Field Team!

Aug. 28, 2020

Despite the current pandemic, the Johnson Lab 2020 Field Team was able to collect host and parasite data from 80 ponds and wetlands in California this summer. Way to go!

California wetlands, Johnson Lab, NSF

Enhancing Integration Between Research and Management

Aug. 28, 2020

Graduate student Wynne Moss and Dr. Johnson were awarded a new supplement through the NSF-INTERN program! This program supports graduate students in collaborating with non-academic entities, for which Wynne will be analyzing amphibian data from agencies in California. Wynne will be working with the East Bay Regional Parks District in...

Erica with her favorite snake

Congratulations to Erica, recipient of the 2020 Fulbright Scholarship!

April 17, 2020

Undergraduate researcher Erica Ursich has recently been awarded a Fulbright Grant to Brazil under the project title, "Snake Assemblage in the Atlantic Forest and the Impact of Edge-effect on Species Prevalence". She will be working with the Institute for Ecological Research, IPÊ (Instituto de Pesquisas Ecológicas) to help begin a...

Lake Isabelle

New Paper! The life aquatic in high relief

Feb. 28, 2020

We are excited to announce a new publication as part of a special issue in Aquatic Sciences on mountain lake ecology. Led by Kelly Loria, the study involved an extensive survey of lakes across an elevational gradient in Colorado's Rocky Mountains. The life aquatic in high relief: shifts in the...

Travis at pond

Phenology Meets Pathology

Feb. 27, 2020

In a newly published article in the Proceedings of the Royal Society Series B , Ph.D. candidate Travis McDevitt-Galles highlights how phenological synchrony between infectious parasites and vulnerable hosts is a key determinant of disease risk, with important implications for forecasted climate shifts. Phenological synchrony shapes pathology in host–parasite systems...

hazel barnes, johnson lab

Hazel Barnes Prize Winner!

June 19, 2019

The Hazel Barnes Prize is the largest and most prestigious award given annually to a CU Boulder faculty member who exemplifies the enriching inter-relationship between teaching and research, and whose work has had a positive impact on students, faculty, colleagues and the university. As noted in the nomination materials, this...

Wynne Moss, Bev Sears Grant, Johnson Lab

Wynne earns Bev Sears grant!

June 19, 2019

Nine EBIO Graduate Students were awarded funding from the Graduate School through the Beverly Sears Grants and our Wynne Moss was one of them! The Bev Sears endowment fund was created to honor Bev Sears in recognition of her longstanding loyalty and efforts on behalf of the Graduate School. Bev...

Brendan Hobat, Johnson Lab

We are growing!

June 19, 2019

Please help us welcome Brendan Hobart to the Johnson Laboratory as our new PhD student! Brendan comes to us from the Peery Wildlife Ecology and Conservation Laboratory at the University of Wisconsin-Madison where he earned a Masters investigating the California spotted owl. Stay tuned to see what Brendan will work...

Tara Stewart Merrill, Johnson Lab

Meet Tara Stewart Merrill our new Post doc!

June 19, 2019

It's offical--Tara Stewart Merrill PhD from University of Illinois Urbana-Champaign will be joining the Johnson Laboratory in August! We are very excited to have Tara for a three year Post Doc where she will investigate how among-and-within- species variation in parasite competence affects the dynamic of infectious disease. Tara was...


A Day in the Field

Nov. 4, 2019

The Johnson Lab joins collaborators from UCSF Medical School (Nadav Ahituv and Jingjing Zhao) in a study to understand how parasites change the development of their hosts using transcriptome approaches.


Cat Parasite Linked to Entrepreneurial Career Choices

Nov. 4, 2019

A new paper coauthored by Stefanie Johnson at the Leeds School of Business and Pieter Johnson links infection by a widespread parasite to entrepreneurial careers in CU students. The paper explores the connection between the protozoan Toxoplasma gondii and patterns of entrepreneurship in students, business professionals and nations. See press...


World's Weirdest Events of BBC

Nov. 4, 2019

In the BBC television show World’s Weirdest Events , the Johnson Lab's research on parasite-induced deformities in amphibians is featured in episode 6, including footage of field and laboratory work as well as a sit-down interview with Dr. Johnson. October 10, 2015 Image by D. Herasimtschuk, Freshwaters Illustrated


Mindsuckers: Meet Nature's Nightmare

Nov. 4, 2019

In the November 2014 issue of National Geographic , the cover story focuses on the capacity of parasites to alter their hosts in bizarre yet fascinating ways. The accompanying story by Carl Zimmer features a broad range of examples, including the ability of the trematode parasite Ribeiroia ondatrae to cause...