Cetacean Notes. I. Sei and Rorqual Whales on the Mississippi Coast, a Correction. II. A Dwarf Sperm Whale in Mississippi Sound and Its Helminth Parasites

I. Gunter and Christmas (1973) described the events leading to the stranding of a baleen whale on Ship Island, Mississippi, in 1968, giving the species as Balaenopteru physalus, the Rorqual. Unfortunately the identification was in error, but fortunately good photographs were shown. The underside of the tail was a splotched white, but there was no black margin. The specimen also had fewer throat and belly grooves than the Rorqual, as a comparison with True’s (1904) photograph shows. Dr. James Mead (in litt.) pointed out that the animal was a Sei Whale, Balaenoptera borealis. This remains a new Mississippi record and according to Lowery’s (1974) count, it is the fifth specimen reported from the Gulf of Mexico. The stranding of a sixth Sei Whale on Anclote Keys in the Gulf, west of Tarpon Springs, Florida on 30 May 1974, was reported in the newspapers and by the Smithsonian Institution (1974). II. Gunter, Hubbs and Beal (1955) gave measurements on a Pygmy Sperm Whale, Kogia breviceps, which stranded on Mustang Island on the Texas coast and commented upon the recorded variations of proportional measurements in this species. Then according to Raun, Hoese and Moseley (1970) these questions were resolved by Handley (1966), who showed that a second species, Kogia simus, the Dwarf Sperm Whale, is also present in the western North Atlantic. Handley’s argument is based on skull comparisons and it seems to be rather indubitable. According to Raun et al. (op. cit.), the stranding of a species of Kogia on Galveston Island recorded by Caldwell, Ingles and Siebenaler (1960) was K. simus. They also say that Caldwell (in litt.) had previously come to the same conclusion. Caldwell et al. also recorded another specimen from Destin, Florida, which is now considered to have been a specimen of simus. The known status of these two little sperm whales in the Gulf is summarized by Lowery (op. cit.).

Community structure and dynamics of Monogenea and Trematoda in three North American cyprinid species in the Salt Valley Watershed, Nebraska.

An investigation was made of the communities of gill monogene genus Dactylogyrus (Platyhelminthes, Monogenea) and the populations of blackspot parasite (Platyhelminthes, Trematoda) of Pimephales promelas, Notropis stramineus, and Semotilus atromaculatus in 3 distinct sites along the 3 converging tributaries in southeastern Nebraska from 2004 to 2006. This work constitutes the first multi-site, multi-year study of a complex community of Dactylogyrus spp. and their reproductive activities on native North American cyprinid species. The biological hypothesis that closely related species with direct lifecycles respond differently to shared environmental conditions was tested. It was revealed that in this system that, Cyprinid species do not share Dactylogyrus species, host size and sex are not predictive of infection, and Dactylogyrus community structure is stable, despite variation in seasonal occurrence and populations among sites. The biological hypothesis that closely related species have innate differences in reproductive activities that provide structure to their populations and influence their roles in the parasite community was tested. It was revealed that in this system, host size, sex, and collection site are not predictive of reproductive activities, that egg production is not always continuous and varies in duration among congeners, and that recruitment of larval Dactylogyrus is not continuous across parasites’ reproductive periods. Hatch timing and host availability, not reproductive timing, are the critical factors determining population dynamics of the gill monogenes in time and space. Lastly, the biological hypothesis that innate blackspot biology is responsible for parasite host-specificity, host recruitment strategies and parasite population structure was tested. Field collections revealed that for blackspot, host size, sex, and collection month and year are not predictive of infection, that parasite cysts survive winter, and that host movement is restricted among the 3 collection sites. Finally, experimental infections of hosts with cercaria isolated from 1st intermediate snail hosts reveal that cercarial biology, not environmental circumstances, are responsible for differences in infection among hosts.

Studies on the Helminth Fauna of Alaska. XIII. Disease in the Sea Otter, with Special Reference to Helminth Parasites

During the spring of 1951, the U. S. Fish and Wildlife Service undertook the removal of sea otter, Enhydra lutris (L)., from the Aleutian Island of Amchitka, for the purpose of restocking range from which the animals have long been exterminated. The decision to undertake this activity was influenced by the nature of military operations planned for the island later the same year. The capture and removal of the otter were under the supervision of Mr. Robert D. Jones, Biologist, U. S. Fish and Wildlife Service. Heavy losses among the animals shortly after capture made the venture unsuccessful. Many deaths were concurrent among animals in the wild state. The writer was asked to investigate the causes of disease in the sea otter, and it is the purpose of this paper to report the results of these investigation, with special reference to helminth parasites.

Studies on the Helminth Fauna of Alaska. XXXVIl. Description of Schizorchis caballeroi n. sp. (Cestoda: Anoplocephalidae), with Notes on Other Parasites of Ochotona

Schizorchis caballeroi n. sp. has been described from the collared pika, Ochotona collaris (Nelson), from Alaska, and has been distinguished morphologically from its congeners, S. ochotonae Hansen, 1948, and S. altaica Gvozdev, 1951. Nine species of helminths have been described 10 dale from North American pikas, O. collaris and O. princeps (Richardson). These mammals are markedly allopatric and do not share any species of helminth. Nematodes of two genera, Eugenuris Shults and Labiostomum Akhtar, 1941, occur in O. collaris as weIl as in palearctic species of Ochotona. This, along with other pertinent information, is taken to suggest that O. collaris has invaded North American more recently than did O. princeps or its precursor.

Parasites and Diseases of Mullets (Mugilidae)

The following treatment of parasites, diseases and conditions affecting mullet hopefully serves several functions. It acquaints someone involved in rearing mullets with problems he can face and topics he should investigate. We cannot go into extensive illustrative detail on every species or group, but do provide a listing of most parasites reported or known from mullet and some pertinent general information on them. Because of these enumerations, the paper should also act as a review for anyone interested in mullet parasites or the use of such parasites as indicators about a mullet's diet and migratory behavior. Unfortunately, limited space prohibits us from presenting all the references used. The paper also deals with the public health aspects of eating or selling mullet, whether the product is to be raw, cooked, salted or smoked.