Paul Jivoff
Visiting Scientist
Rider University, Lawrenceville, NJ

Research Interests
My general interests include behavioral ecology and animal behavior with an emphasis on the evolution of behavior. I am particularly interested in mating behavior, sexual competition, and mate choice. My previous work tested hypotheses for the evolution of both pre- and post-copulatory mate guarding in the blue crab. The results led to a new hypothesis for the influence of exploitation (predominantly on male crabs) on blue crab reproduction, which states that intense removal of males from the population limits female reproduction. Currently, I am collaborating with Tuck Hines, from the Smithsonian Environmental Research Center and Tom and Donna Wolcott, from the North Carolina State University, to test this hypothesis by examining the potential for fisheries-induced sperm limitation, within and among populations differing in fishing pressure, and its influence on female reproductive output in blue crabs. I am also interested in the factors that influence female mating success. I have examined the importance of female characteristics including female size, mating history, physical condition (e.g., limb loss) and physiological condition (e.g., proximity to molt) on brood production in a species of mud crab (Xanthidae). Also in collaboration with Tuck Hines and colleagues at the Center of Marine Biotechnology in Baltimore, we are testing the effects of both environmental and female characteristics on the timing, frequency and extent of female brood production in blue crabs.

More recently, I have become interested in habitat use particularly as a measure of habitat quality and the potential interactions between species. I am comparing aspects of blue crab populations (e.g., size, sex ratio, molting) in newly restored marshes with those in adjacent reference marshes in Delaware Bay to estimate the effectiveness of marsh restoration. I am also interested in the effect of invasive species on native species and habitats. One aspect of the marsh restoration project in Delaware Bay examines the response of blue crabs to the removal of the invasive common reed (Phragmites) and the re-introduction of native marsh vegetation (Spartina). In collaboration with Greg Ruiz and Cat deRivera, from the Smithsonian Environmental Research Center, and with the help of undergraduate interns from University of Maryland, University of Minnesota and Rider University, we are testing hypotheses for the regional spread (see Figure 1) and local habitat use (see Figure 2) of the invasive European green crab, Carcinus maenas, along the east coast of North America, including environmental characteristics (e.g. temperature), and interactions (e.g., competition and predation) with native species (e.g., blue crab).

Publications

Journal Articles

• Jivoff, P. 1997. The relative roles of predation and sperm competition on the duration of the post-copulatory association between the sexes in the blue crab, Callinectes sapidus. Behavioral Ecology and Sociobiology 40: 175-185.
• Jivoff, P. 1997. Sexual competition among male blue crab, Callinectes sapidus. Biological Bulletin 193: 368-380.
• Jivoff, P. and Hines, A.H. 1998. Female behavior, sexual competition and mate guarding in the blue crab, Callinectes sapidus. Animal Behaviour 55: 589-603.
• Jivoff, P. and Hines, A.H. 1998. The effect of female molt stage and sex ratio on courtship behavior in the blue crab, Callinectes sapidus. Marine Biology 131: 533-542.
• Jivoff, P. and Able, K.W. 2001. Characterization of the fish and selected decapods in Little Egg Harbor. Journal of Coastal Research.
• Jivoff, P. Accepted. A review of male mating success in the blue crab, Callinectes sapidus, in reference to the potential for fisheries-induced sperm limitation. Bulletin of Marine Science.
• Jivoff, P. Accepted. Summary Paper: Reproduction and Embryonic Development Session, Blue Crab Symposium 2000. Bulletin of Marine Science.
• Hines, A.H., Jivoff, P.R., Bushmann, P.J., van Montfrans, J., Reed, S.A., Wolcott, D.L. and Wolcott, T.G. Accepted. Evidence for sperm limitation in the blue crab, Callinectes sapidus. Bulletin of Marine Science.
• Jivoff, P. and Able, K.W. In Review. Evaluating salt marsh restoration in Delaware Bay: The response of blue crabs, Callinectes sapidus, at former salt hay farms. Estuaries.
• Jivoff, P. and Able, K.W. In Review. Blue crab, Callinectes sapidus, response to the invasive common reed, Phragmites australis: Abundance, size, sex ratio, and molting frequency. Estuaries.
• Jivoff, P., Able, K.W. and Martino, E. In Review. Identifying "essential" habitats of blue crabs Callinectes sapidus from inter- and intra-estuarine variability in habitat use. Marine Ecology Progress Series.

  Book Chapters
  

• Jivoff, P., Hines, A.H., Quackenbush, S. Accepted. Reproduction Biology and Embryonic Development. In: The Blue Crab, Callinectes sapidus. V. Kennedy (ed). Maryland Seagrant, College Park MD.

  Reports
  

• Jivoff, P., Bochenek, E. and Reid, R. Fisheries of Barnegat Bay. 2001. In: Characterization Report of Barnegat Bay. EPA Barnegat Bay Estuary Program

Contact Information
Paul Jivoff
Assistant Professor
Department of Biology
Rider University
2083 Lawrenceville Rd
Lawrenceville, NJ 08648
TEL: 609-895-5421
FAX: 609-895-5782
e-mail: pjivoff@rider.edu
webpage: http://enigma.rider.edu/~wwwbio/jivoff.html