Diamondback

Abstract: xii, 219 pages, 12 unnumbered pages of plates : illustrations (some color) ; 24 cm Contents: A decidedly unique creature -- A coast-hugging turtle -- Reproduction : insurance for species survival -- The lost years -- A clear and present danger for the most celebrated of American reptiles -- Learning from the past; peering into the future. Includes bibliographical references (pages 205-214) and index. Full jacket text: The first book-length investigation of a fascinating turtle She’s the mascot for the University of Maryland’s sports teams (their slogan: Fear the Turtle) and her ancestors were nearly driven to extinction by Victorians who indulged in turtle soup. But as she buries herself in the mud every night to sleep, the diamondback terrapin knows none of this. The size of a dinner plate, with a lifespan of at least forty years, she is the only turtle in North America who can live in brackish and salty waters. The diamondback terrapin is named for the beautiful concentric rings on its shell. Its habitat ranges from Cape Cod to Corpus Christi,Texas, with seven subspecies identified along the Atlantic and Gulf coasts. Several diamondback populations have been the subjects of ecological studies in recent years, but most of that information was buried in scientific literature and various state and federal reports—until now. Synthesizing all known research on this remarkable animal, Diamonds in the Marsh is the first full-scale natural history of the diamondback terrapin. Focusing on the northern diamondback, Barbara Brennessel examines its evolution, physiology, adaptations, behavior, growth patterns, life span, genetic diversity, land use, reproduction, and early years. She also discusses its relationship to humans, first as an important food source from colonial times through the nineteenth century, and more recently as a cultural icon, frequently depicted in Native American art and design. She concludes with a look at contemporary hazards to the terrapin, and urges continued study of this marvelous creature.

Abstract: The effects of pesticides on the diamondback moth, Plutella xylostella (L.), and parasitism by Diadegma insulaTe (Cresson) was studied at the Michigan State University Entomology Research Farm during July and August 1990. The range of diamondback moth parasitism from three different locations in Michigan was 60.8–83.3%. Pesticides used were Bacillus thuringiensis var. Kurstaki (Berliner), thiodicarb, thiodicarb + B. thuringiensis , chlorpyrifos, permethrin, ICIA 0321 (pyrethroid), and esfenvalerate. Diamondback larval moth mortality was not Significantly different among the treated plots but was significantly higher than in untreated plots 3 d after spraying. The change in number of diamondback moth larvae (0 versus 3 d), and diamondback moth and D. insulare pupae (0 versus 6 d) was similar in all treatments. Parasitism by D. insulare in treated plots was not affected 6 d after spraying with any pesticide tested. Mean percentage parasitism by D. insulare in guard rows was also not different. However, the percentage parasitism in cages 3 d after treatment with permethrin, azinphosmethyl, or B. thuringiensis or untreated was 7.8, 13.3, 81.5, and 79.4%, respectively. Parasitism by D. insulare of the diamondback moth larvae seems to be influenced by the vegetation or refuge plants present outside the experimental plots. Diamondback moth parasitism by D. insulare may not be affected severely if pesticides are judiciously used.

Abstract: A simple, inexpensive method of mass-rearing diamondback moths, Plutella Xylostella , by a modification of an existing technique using rape seedlings is described.