Welcome to Judith Weis’s Personal Website!


Most of our research focuses on the effects of stressors like environmental contaminants, invasive species, and parasites on the behavior and ecology of estuarine organisms. We are interested in responses at the organismal level, such as changes in development, growth, or behavior; responses at the population and community level, such as the development of tolerance on the part of populations that are chronically exposed to certain pollutants, altered life histories, alterations in predator/prey interactions and trophic transfer of contaminants.

Epifauna that live on stems seem to prefer Spartina, as do mummichogs that utilize the marsh surface at high tide. Some of this work is being done in conjunction with the Meadowlands Environmental Research Institute, MERI, which supports joint research projects of several faculty members and is sponsored by the New Jersey Meadowlands Commission (NJMC).


We are interested in the role of salt marsh plants in providing nutrition and transferring toxicants to animals. We are comparing the native marsh plant, Spartina alterniflora with the invasive reed, Phragmites australis in terms of their use as habitat by fiddler crabs, grass shrimp and larval mummichogs, and their nutritional value to the marsh invertebrates. We are also comparing metal uptake, storage and release by these two plants in the Hackensack Meadowlands. Data gathered thus far indicate that Spartina accumulates and releases greater amounts of metals than Phragmites, and that the two plants seem to be equivalent as food, once they have been converted to detritus, and to serve the same habitat function for some but not all of the animals.

The proximity to the Hackensack Meadowlands and Newark Bay, which is a severely stressed estuary, gives us a convenient "outdoor laboratory." We have found such tolerance to methylmercury in populations of mummichogs (Fundulus heteroclitus), grass shrimp (Palaemonetes pugio) and fiddler crabs (Uca pugnax) from the northern NJ estuaries, but have also found that enhanced tolerance comes at a price. We are currently looking at impaired feeding behavior in these fish. They are less capable of capturing live prey, and consequently eat higher proportions of sediment and detritus, which are not nutritious. The reduced prey capture is associated with lower general activity level and reduced levels of serotonin in their brains. We are also looking into the possible involvement of the thyroid gland in their low activity level. This may be a case of endocrine disruption caused by environmental contaminants. Their poor diet may be partly responsible for their decreased growth and life span. However, their prey organisms, grass shrimp (Palaemonetes pugio), whose predator-avoidance does not seem to be impacted by the contaminants in the polluted environment, may be benefiting from being preyed upon less. They are larger in size as well as more numerous at the contaminated site.

"Tall green grass. Subtle melodies of songbirds. Sharp whines of muskrats. Rustles of water running through the grasses. And at low tide, a pungent reminder of the treasures hidden beneath the surface. All are vital signs of the great salt marshes' natural resources.

Now championed as critical habitats for plants, animals, and people because of the environmental service and protection they provide, these ecological wonders were once considered unproductive wastelands, home solely to mosquitoes and toxic waste, and mistreated for centuries by the human population. Exploring the fascinating biodiversity of these boggy wetlands, Salt Marshes offers readers a wealth of essential information about a variety of plants, fish, and animals, the importance of these habitats, consequences of human neglect and thoughtless development, and insight into how these wetlands recover.

Judith S. Weis and Carol A. Butler shed ample light on the human impact, including chapters on physical and biological alterations, pollution, and remediation and recovery programs. In addition to a national and global perspective, the authors place special emphasis on coastal wetlands in the Atlantic and Gulf regions, as well as the San Francisco Bay Area, calling attention to their historical and economic legacies.

Written in clear, easy-to-read language, Salt Marshes proves that the battles for preservation and conservation must continue, because threats to salt marshes ebb and flow like the water that runs through them."- Rutgers University Press

"Weis and Butler turn Teal's classic story of the life and death of the salt marsh into a story of rebirth, with a compelling narrative about salt marsh restoration. A good resource and a pleasure to read. Salt Marshes: A Natural and Unnatural History is a well-written and compelling narrative of the past, present, and future states of salt marshes. The book is both scholarly and timely, and it outlines what is at stake if we do not tend to these threatened and ecologically important habitats."—BioScience Magazine, June 2010 (from the Rutgers University Press website)

"The authors provide a detailed account of the biodiversity of salt marshes and the tremendous benefits that they provide to the natural world. By enhancing understanding of the benefits of these areas, the damage caused to coastal marshes may be avoided in the future if we remain vigilant."—Wildlife Activist (from the Rutgers University Press website)

"Salt Marshes: A Natural and Unnatural History" by Judith S. Weis and Carol A. Butler


"Salt Marshes: A Natural and Unnatural History" by Judith S. Weis and Carol A. Butler


"Do Fish Sleep?" by Judith S. Weis

"Do Fish Sleep?: Fascinating Answers to Questions about Fish" by Judith S. Weis"


A photo of me taken at the Accabonac Harbor salt marshes in East Hampton, NY.

Praise for Do Fish Sleep?

"Judith Weis's clearly written book will interest a wide range of readers, from educators to naturally curious young people."—Howard Reisman, Professor Emeritus of Biology, Long Island University

"Do Fish Sleep? must have every Ichthyology 101 final exam question imaginable, but with much more thorough and engaging answers!"—Francis Juanes, University of Massachusetts

"Fish, fish, and more fish--from minnows to sharks, mountain streams to ocean bottoms, and teeth to tail fins, if it's a fish question, it's answered here."—John Waldman, author of Heartbeats in the Muck: The History, Sea Life, and Environment of New York Harbor

From the fifty-one-foot whale shark Rhincodon typus to a less-than-one-half-inch fish in the minnow family--the tiny Paedocypris progenetica--fish certainly carry a lot of weight . . . or do they?

A fish's heft in water may vary, but these diverse aquatic animals certainly carry a lot of weight in our ecosystems and environment. From freshwater to ocean habitats, Judith S. Weis offers a fascinating look at these deceptively simple creatures. Fishes may appear to live a dull existence, but appearances change once we understand more about how they survive. These wonders actually possess attributes that would make us superpowers--they can change color, sex, produce light and electricity, regenerate injured fins, prevent themselves from sinking, and some can even walk on land.

Do Fish Sleep? is organized in an easy-to-read and accessible question-and-answer format, filled with more than 55 photographs and over 100 interesting facts from fish biology basics to the importance of preserving and restoring fish diversity and healthy populations. A captivating read for fish enthusiasts of all ages--naturalists, environmentalists, aquarists, scuba divers, and students--this is also the perfect primer for those just about to get their feet wet. Dive in!

“Walking Sideways; The Remarkable World of Crabs” by Judith S.Weis

The world's nearly 7,000 species of crabs are immediately recognizable by their claws, sideways movement, stalked eyes, and thick outer shells. These common crustaceans are found internationally, thriving in various habitats from the edge of the sea to the depths of the ocean, in fresh water or on land. Despite having the same basic body type as decapod crustaceans—true crabs have heavy exoskeletons and ten limbs with front pincer claws—crabs come in an enormous variety of shapes and sizes, from the near microscopic to the giant Japanese spider crab.

In Walking Sideways, Judith S. Weis provides an engaging and informative tour of the remarkable world of crabs, highlighting their unique biology and natural history. She introduces us to recently discovered crabs such as the Yeti crab found in deep sea vents, explains what scientists are learning about blue and hermit crabs commonly found at the shore, and gives us insight into the lifecycles of the king and Dungeness crabs typically seen only on dinner plates. Among the topics Weis covers are the evolution and classification of crabs, their habitats, unique adaptations to water and land, reproduction and development, behavior, ecology, and threats, including up-to-date research.

Crabs are of special interest to biologists for their communication behaviors, sexual dimorphism, and use of chemical stimuli and touch receptors, and Weis explains the importance of new scientific discoveries. In addition to the traditional ten-legged crabs, the book also treats those that appear eight-legged, including hermit crabs, king crabs, and sand crabs. Sidebars address topics of special interest, such as the relationship of lobsters to crabs and medical uses of compounds derived from horseshoe crabs (which aren't really crabs).

While Weis emphasizes conservation and the threats that crabs face, she also addresses the use of crabs as food (detailing how crabs are caught and cooked) and their commercial value from fisheries and aquaculture. She highlights other interactions between crabs and people, including keeping hermit crabs as pets or studying marine species in the laboratory and field. Reminding us of characters such as The Little Mermaid's Sebastian and Sherman Lagoon’s Hawthorne, she also surveys the role of crabs in literature (for both children and adults), film, and television, as well in mythology and astrology. With illustrations that offer delightful visual evidence of crab diversity and their unique behaviors, Walking Sideways will appeal to anyone who has encountered these fascinating animals on the beach, at an aquarium, or in the kitchen.


“Physiological, Developmental and Behavioral Effects of Marine Pollution” by Judith S. Weis




Synthesizing decades of work, but up-to-date, this book focuses on organism-level responses to pollutants by marine animals, mainly crustaceans, molluscs, and fishes. Emphasizing effects on physiological processes (feeding/digestion, respiration, osmoregulation), life-cycle (reproduction [including endocrine disruption], embryo development, larval development, developmental processes later in life (growth, regeneration, molting, calcification, cancer), and behaviour, the book also covers bioaccumulation and detoxification of contaminants, and the development of tolerance. The major pollutants covered are metals, organic compounds (oil, pesticides, industrial chemicals), nutrients and hypoxia, contaminants of emerging concern, and ocean acidification. Some attention is als     o devoted to marine debris and noise pollution.



“Marine Pollution What Everyone Needs to Know®” by Judith S. Weis






"Biological Invasions and Animal Behaviour"

  EDITORS: Judith S. Weis, Rutgers University, New Jersey & Daniel Sol, National Spanish Research Council (CSIC)