Ecology and Evolutionary Biology Commons^™

An Interactive Application For Tracking The Movement Of The Limulus Polyphemus Throughout Long Island Sound (Lis), Ismael Youssef, Samah Senbel, Jennifer Mattei

Biology Faculty Publications

Poster presented at the Long Island Sound Research Conference held March 15, 2019 in Port Jefferson, New York.

Conservation Status Of The American Horseshoe Crab, (Limulus Polyphemus): A Regional Assessment, David R. Smith, H. Jane Brockmann, Mark Beekey, Timothy L. King, Michael J. Millard, Jaime Zaldívar-Rae

Biology Faculty Publications

Horseshoe crabs have persisted for more than 200 million years, and fossil forms date to 450 million years ago. The American horseshoe crab (Limulus polyphemus), one of four extant horseshoe crab species, is found along the Atlantic coastline of North America ranging from Alabama to Maine, USA with another distinct population on the coasts of Campeche, Yucatán and Quintana Roo in the Yucatán Peninsula, México. Although the American horseshoe crab tolerates broad environmental conditions, exploitation and habitat loss threaten the species. We assessed the conservation status of the American horseshoe crab by comprehensively reviewing available scientific information on its range, …

The Mismanagement Of Limulus Polyphemus In Long Island Sound, U.S.A.: What Are The Characteristics Of A Population In Decline?, Mark Beekey, Jennifer Mattei

Biology Faculty Publications

Over the past 15 years, horseshoe crabs in Connecticut have gone from being considered a nuisance species to a species of Greatest Conservation Need in 2015. This has happened through first, its discovery as an economically important species, second through research of its ecological role in coastal estuaries, and third, through education of the public concerning its role in the environment and their own health. To manage horseshoe crab populations successfully requires long term monitoring, research and education. The use of annual or biannual trawl data trends to assess the success of management decisions is limited due to the high …

Horseshoe Crab Research In Urban Estuaries: Challenges And Opportunities, Jennifer Mattei, Mark L. Botton, Mark Beekey, Christina P. ColóN

Biology Faculty Publications

Horseshoe crabs rely on estuaries for food resources, places to spawn and for larvae and juveniles to develop and grow. Many of these estuaries are becoming increasingly urbanized and dominated by human activity. An urban estuary is characterized by armored shorelines, high nutrient loads, large fluctuations in algal and bacteria populations, increased levels of pollutants like heavy metals and pesticides, and seasonally low oxygen levels and pH. While urban estuaries are challenging for horseshoe crab survival and to researchers trying to study them, there are also opportunities for involving the public in research and increasing public awareness of the importance …

Horseshoe Crab Eggs: A Rare Resource For Predators In Long Island Sound, Mark Beekey, Jennifer Mattei, Barbara J. Pierce

Biology Faculty Publications

In Delaware Bay, the spawning of several million horseshoe crabs (Limulus polyphemus) coincides with the arrival of migratory shorebirds that feed on their eggs. High horseshoe crab spawning densities and resulting high egg densities drive egg availability and predation rates. At high spawning densities, female horseshoe crabs perturb previously deposited clutches causing eggs to rise to the sediment surface (surface egg densities average 100,000 eggs m^{− 2}). At the surface (0–5 cm), the eggs are quickly depleted by shorebirds and other predators. This interaction between egg density and egg predation has not been explicitly explored on …

A Comparison Of Prairie Vole Audible And Ultrasonic Pup Calls And Attraction To Them By Adults Of Each Sex, Thomas A. Terleph

Biology Faculty Publications

Rodent pups of many species emit both ultrasonic vocalizations (USVs) and calls spanning into a lower frequency range, audible to humans (AUDs), yet there has been little systematic comparison of these different call types, or analyses of how they might differ in signal function. Here the spectral and temporal characteristics of USV and AUD pup calls are described for the prairie vole (Microtus ochrogaster), a model used in studies of monogamous mating and biparental care, and a species with an unusually large functional and anatomical representation of auditory cortex. Findings provide a detailed description of each call type, …

Estimation Of Short-Term Tag-Induced Mortality In Horseshoe Crabs Limulus Polyphemus, Jennifer Mattei, Mark Beekey, H. R. Potter, C. S. Bond, Alyssa Woronik, J. A. Roberts, K. A. Smith

Biology Faculty Publications

Horseshoe crabs Limulus Polyphemus range along the East Coast of the United States and over 150,000 of them have been marked with U.S. Fish and Wildlife Service disk tags. It has been assumed that the tags do not harm the animals and are similar to common epibionts often found on the shells of the horseshoe crabs. We investigated whether newlv tagged adult female horseshoe crabs would exhibit higher short-term mortality rates than untagged adult females. All crabs were collected from a beach in Connecticut and then were transported to a laboratory for the experiment. Tagging involved drilling a small hole …

The Ratio Of Gametophytes To Tetrasporophytes Of Intertidal Chondrus Crispus (Gigartinaceae) Across A Salinity Gradient, Michele Guidone, Sean Grace

Biology Faculty Publications

Population studies of the Gigartinaceae (Rhodophyta) have often observed that the ratio of gametophytes to tetrasporophytes varies with the location of the population or the time of sampling. For some species, patterns have emerged that correlate this ratio to one or a few particular environmental variables, such as elevation, wave exposure, or season. Identifying these distributional patterns is an important step towards understanding what (if any) ecological differences exist between the two free-living life history stages.

The purpose of this study was to measure the ratio of gametophytes to tetrasporophytes of intertidal populations of Chondrus crispus across a decreasing salinity …

Reproductive Behavior In Horseshoe Crabs: Does Density Matter?, Jennifer Mattei, Mark Beekey, Adam Rudman, Alyssa Woronik

Biology Faculty Publications

While the four species of horseshoe crabs share many common reproductive traits with respect to their reproductive systems, they do differ with respect to their mating behavior (monogamy vs. polygynandry). Past research has attributed these differences to a number of factors including: spawning densities, operational sex ratios (OSR’s), male condition (or age), environmental and/or genetic factors, or a combination thereof. Mating behaviors in the three Asian horseshoe crab species (Tachypleus gigas , T. tridentatus, and Carcinoscorpius rotundicauda ) with low spawning densities and 1:1 operational sex ratios are typically monogamous. In Limulus polyphemus , mating behavior is more …

Movement Patterns And Population Genetics Of The American Horseshoe Crab In Relation To Long Island Sound Conservation Strategies, Jo-Marie Kasinak, Kirk A. Bartholomew, Mark Beekey, Jennifer Mattei

Biology Faculty Publications

The Connecticut Department of Environmental Protection (CTDEP) established three no-harvest zones for the horseshoe crab (Limulus polyphemus) population as part of a conservation plan for the species. Data from a long-term mark/recapture study of horseshoe crabs in conjunction with a microsatellite-based genetic survey of the population were analyzed to determine if this plan was appropriate to conserve genetic diversity and broaden our knowledge of movement patterns of Limulus in Long Island Sound (LIS). To date, ~53,000 crabs have been tagged over a 10 year period through the Project Limulus program with an annual average recapture rate of 12 …

The Horseshoe Crab Conundrum: Can We Harvest And Conserve?, Jennifer Mattei, Mark Beekey

Biology Faculty Publications

Horeshoe crabs "Limulus polyphemus" are remarkable ‘living fossils’ which have unique blood cells (amebocytes) that are used to test human vaccines for bacterial contamination. In the 1950’s, scientists at the Marine Biological Laboratory in Woods Hole, Massachusetts, not only discovered amebocytes but also found that they had special properties. If the amebocytes came into contact with bacteria, they would instantly coagulate around the bacteria and attack it. The Woods Hole scientists took this unique property of horseshoe crabs and developed a test for bacterial contamination using a horseshoe crab blood derivative called Limulus Amebocyte Lysate (LAL).

This article describes discusses …

Project Limulus: What Long-Term Mark/Recapture Studies Reveal About Horseshow Crab Population Dynamics In Long Island Sound, Mark Beekey, Jennifer Mattei

Biology Faculty Publications

Project Limulus is a long-term study of the population dynamics of the horseshoe crab population in Long Island Sound (LIS). We have tagged over 20,000 spawning adults from >20 beaches ranging from Greenwich to Stonington, CT since 1997. Cumulative recapture rates have reached 9%. On average 90% of the crabs are recaptured within a few miles of their original tag site within the first season. Between seasons, on average, 45% of crabs are recaptured within the same locality of where they were tagged. Of all recaptures, 99% of recaptured individuals are found within LIS. This past year we expanded the …

Eleutherodactylus Ridens (Pygmy Rainfrog) Predation, Tobias Eisenberg, Twan Leenders

Biology Faculty Publications

Workers of the large ponerine ant Paraponera clavata typically forage on small to medium-sized arthropods or collect pieces of plants or nectar but have been suspected of predating small vertebrates.

New Distribution Records For Amphibians And Reptiles In Connecticut, With Notes On The Status Of An Introduced Species, Gregory J. Watkins-Colwell, Twan Leenders, Brian T. Roach, Daniel J. Drew, Gregg Dancho, Jeanne Yuckienuz

Biology Faculty Publications

Recent field work and a review of catalogued specimens in the herpetology collections at the Yale Peabody has yielded 170 new town records for amphibians and reptiles in Connecticut. These are reported here, along with observations on the status of the red-ear slider (Trachemys scripta) in Connecticut.

Negative Effect Of Zebra Mussels On Foraging And Habitat Use By Lake Sturgeon (Acipenser Fulvescens), D. J. Mccabe, Mark Beekey, A. Mazloff, I. E. Marsden

Biology Faculty Publications

1. Lake sturgeon (Acipenser fulvescens) are threatened or endangered throughout much of their range. Juvenile sturgeon utilize sandy and silty habitats extensively during their growth. Invasive zebra mussels change the nature of sandy and silty habitats because they settle on and coat the habitat with the shells of living and dead individuals. The potential impacts of this increased habitat complexity on lake sturgeon is unknown. 2. Juvenile lake sturgeon habitat choice was assessed in laboratory experiments, and zebra mussel impact on the foraging success of juvenile lake sturgeon on three different prey species was measured. 3. Sturgeon foraging on chironomids …

Apparent Sibling Rivalry In The Freshwater Clam Sphaerium Striatinum, Mark Beekey, Ronald H. Karlson

Biology Faculty Publications

In Sphaerium striatinum, a freshwater brooding bivalve, up to 97.5% of offspring that adults initially produce fail to reach independence. Marsupial sacs, specialized extensions of gill filaments that act as nurseries, initially contain multiple offspring in various sizes and stages of development. However, by the time offspring reach later stages of development, marsupial sacs typically contain only one offspring. Brood mortality is hypothesized to be the result of competition among embryos for nutrients and/or space. Sphaeriid eggs do not contain enough yolk for offspring to complete development. Adults supply additional nutrients required to reach independence. Brood capacity is limited by …

Zebra Mussels Affect Benthic Predator Foraging Success, Mark Beekey, D. J. Mccabe, I. E. Marsden

Biology Faculty Publications

The introduction of zebra mussels (Dreissena spp.) to North America has resulted in dramatic changes to the complexity of benthic habitats. Changes in habitat complexity may have profound effects on predator-prey interactions in aquatic communities. Increased habitat complexity may affect prey and predator dynamics by reducing encounter rates and foraging success. Zebra mussels form thick contiguous colonies on both hard and soft substrates. While the colonization of substrata by zebra mussels has generally resulted in an increase in both the abundance and diversity of benthic invertebrate communities, it is not well known how these changes affect the foraging efficiencies of …

Effect Of Food Availability On Reproduction And Brood Size In A Freshwater Brooding Bivalve, Mark Beekey, Ronald H. Karlson

Biology Faculty Publications

Brood size is often constrained by the amount of energy available to produce offspring. Yet, energetic constraints may not be as important if the physical capacity to brood offspring is limited. Investigating the relative importance of energetic and physical constraints on brood size is necessary to understand how reproductive strategies are molded by natural selection. We investigated how food availability affects brood size in Sphaerium striatinum, a freshwater bivalve. We reared juveniles to adulthood under three food levels in a common garden experiment. The number of reproductive attempts, brood size, and stage of offspring development were measured. Clams reared …

Parental Care In Sphaerium Striatinum Lamarck: Evidence For Retention Of Competent Offspring, Mark Beekey, Ronald H. Karlson, Alyse R. Greenberg

Biology Faculty Publications

The timing of offspring release is a fundamental turning point in the life history of any organism. It represents the end to many of the most costly forms of parental care (e.g., provisioning of nutrients for developing eggs and zygotes) and the beginning of an independent life for the offspring. Generally temporal variation in this event is attributed to a variety of physiological and evolutionary trade-offs. Here we examine the retention of offspring in the freshwater clam Sphaerium striatinum Lamarck. Brooded offspring are typically not released into the environment until they are 4.0 mm shell length (SL). We provide evidence …

Does The Water Dragon, Physignathus Lesueurii (Gray 1831), Occur In New Guinea?, Gregory J. Watkins-Colwell, Greg Johnston

Biology Faculty Publications

The Australian water dragon, Physignathus lesueurii (Gray 1831), is a large acrodontan lizard which occurs in eastern Australia and has been reported from western New Guinea (Fig. 1). The species appears to be absent from eastern New Guinea (Allison 1982).