Watershed Ecology

Surbering & Flowmeter

The objectives of the Patrick Center’s Watershed and Systems Ecology Section are to understand, conserve and restore aquatic ecosystems using a “systems” perspective. The center has considerable expertise to do this, which includes field and laboratory studies that focus on analyzing and simulating the structure and function of stream, riverine, and lacustrine ecosystems at multiple spatial scales. Our section develops and applies spatial models that will be useful tools for watershed managers.

Clear here to learn more about our staff.

Click here to visit our Macroinvertebrate Lab webpage.


  • Stream channel and hydrologic surveys
  • Spatial simulation of stream hydraulics
  • Spatial analyses and mapping using geo- and spatial autoregressive- statistics
  • Aquatic invertebrate, fish, and periphyton respirometry, and bioenergetic modeling
  • Simulation of the dynamics, disruption, and development of aquatic ecosystems
  • Multi-scale (micro-, reach-, and watershed- scale) analyses of stream networks
  • Biophysical and ecological economic analyses of ecosystem services.


The Watershed and Systems Ecology Section builds upon The Academy’s diverse set of skills in systematics, ecology, and education. It also has access to a variety of sampling gear, vehicles, laboratory equipment, and other facilities to complete large, multidisciplinary studies.

Section Facilities

  • Geographic modeling laboratory with programming, GIS, and statistical software
  • Survey gear including Total station, GPS base station, and water velocity meters
  • ARGGIS 9.3 and related spatial analysis software
  • Database of streams in the Delaware Basin at the riparian- and watershed- scale
  • Respirometry laboratory for the development of bioenergetic models

Patrick Center and Academy Facilities

  • Vehicles such as motor boats and trucks
  • Field sampling equipment for fish, macroinvertebrates, plankton, and epiphyton
  • Fisheries laboratory (fish identification, aging using scales or otoliths)
  • Library and collections of biota
  • Sediment and water chemistry laboratories
  • Variety of microscopes and dissecting scopes

Selected Projects

Delaware River Watershed Initiative
P.I. -Stefanie Kroll, Ph.D.
The Delaware River Watershed Initiative (DRWI) is an unprecedented collaboration to protect and restore water quality in the Delaware River watershed. More than 50 leading nonprofits have joined together to accelerate conservation in eight regions of the watershed. Informed by science, the Initiative implements land protection and restoration projects in these eight ecologically significant areas. As the scientific lead for the DRWI, the Academy helps prioritize areas for on-the-ground work, designs and coordinates stream monitoring efforts at more than 300 sites throughout the watershed, and analyzes data to assess the impacts of DRWI protection and restoration projects on stream water quality.
Assessment of Past Restoration Projects in Southeast PA, 2015 - 2018 – PA DEP Growing Greener
P.I. -Stefanie Kroll, Ph.D.
Stream restoration projects (streamside vegetation plantings, modified stormwater basins, stream fencing, stream channel modification, etc.) have been completed throughout the Delaware River watershed over the past 20 years, with a goal of improving aquatic habitat and/or water quality. From 2002 to 2006, Academy scientists studied the streams where these restoration projects had been implemented, using biological, chemical, and physical analyses to determine changes in aquatic habitat and water quality in relation to the completed project. The Watershed Ecology section builds on this study by surveying those previously-studied restoration project sites (now 12-20 years old), as well as sites restored more recently (5-10 years old). Results will be analyzed and applied to current and future restoration and monitoring efforts.
Assessing restoration outcomes in aquatic habitat and biotic communities in MD and PA – Maryland Sea Grant
P.I.s –Matthew Baker, Ph.D. (University of Maryland, Baltimore County) & Haley Oakland
Collaborator –Stefanie Kroll, Ph.D.

Utilizing preliminary outcomes from the Academy’s PA DEP Growing Greener project (Assessment of Past Restoration Projects in Southeast PA, 2015-2018), UMBC and the Academy’s Watershed Ecology section collaborate to study restoration projects in Pennsylvania and Maryland. While the restoration project assessments in Southeast PA take a close look at stream chemistry and biological communities (algae, fish, aquatic insects, etc.), this study combines those traditional assessments of aquatic habitat and biota with remote sensing techniques to attempt to improve the ability to measure changes in stream ecosystems, and understand relationships between biological communities and habitat post-restoration.
Wissahickon Valley Park – Habitat Management Plan
P.I.s – Will Ryan, Ph.D. & Richard Horwitz, Ph.D.
Friends of the Wissahickon has contracted the Academy of Natural Sciences to collaborate on creating the Wissahickon Valley Park (WVP) Habitat Management Plan. In 1999, the Fairmount Park Commission selected the Academy of Natural Sciences to work on the Natural Lands Restoration and Environmental Education Program (NLREEP), which resulted in the creation of the WVP Master Plan. We will evaluate gaps in data from the WVP, and identify, define and prescribe best management practices for ecological restoration and maintenance of ecosystem integrity, with special attention to locations in the park for which the actions are appropriate. In addition, we will describe appropriate monitoring techniques to quantify improvements in and/or maintenance of environmental conditions. Lastly, we will suggest research avenues that could further elucidate the complex ecological interactions present in the WVP.
Existing Conditions Report on Wissahickon Creek in the Whitemarsh Valley
P.I. – Will Ryan, Ph.D.
As the Wissahickon Creek flows through the limestone-rich Whitemarsh Valley, it passes through a culturally rich landscape, including Ft. Washington State Park, Erdenheim Farm, and Morris Arboretum. A number of stressors impact stream water quality (e.g., upstream impervious surfaces, obstructions, invasive species, and point-source pollutants) in this watershed. We have embarked on a multi-year project which aims to assess the current ecological and environmental conditions of the Creek. As we begin to analyze results, we will develop strategies to address local-scale factors, which, if dealt with, have the potential to ameliorate conditions in the Wissahickon Creek.
Lentic Habitats
P.I. – Meghan O’Donnell
Lentic habitats are areas in a stream with little to no flow. This study aims to assess possible relationships between agricultural land use, aquatic insect communities and habitat quality of these in-stream “pools” in agriculturally dense landscapes in the Schuylkill and Christina river watersheds. When studying aquatic insects for use as indicators of stream ecosystem integrity, samples are often only taken from riffle areas, because riffles typically display the greatest species diversity. In lentic areas, agricultural runoff that carries excess fertilizer into the streams may affect oxygen, sediment deposition, and temperature differently than in lotic (flowing) areas. In lentic habitats, we find taxa that are often absent in riffles, with a high percentage of predators and air-breathing species. We are also interested in whether watershed size plays a role in the relationships between habitat quality and community composition.