Gastrointestinal helminths of the northern bobwhite in Florida: 1968 and 1983

We collected 153 northern bobwhites (Colinus virginianus) over a 10-mo period from Tall Timbers Research Station near Tallahassee, Florida, USA. Five species of gastrointestinal helminths were encountered commonly (greater than 30% prevalence): Cyrnea colini, Raillietina cesticillus, R. colinia, Heterakis isolonche, and Trichostrongylus tenuis. Other helminths included Brachylaima sp., Rhabdometra odiosa, Mediorhynchus papillosis, Cheilospirura spinosa, Dispharynx nasuta, Gongylonema ingluvicola, and Tetrameres pattersoni. During the intervening 15 yr since the last year-round study of this population of birds, C. spinosa and T. pattersoni have declined markedly, and Strongyloides sp. probably has become extinct locally. Prevalence and intensity seem more likely to fluctuate in parasite species that have complex life cycles.     

Factors affecting the helminth community structure of adult collared peccaries in southern Texas

Four species of nematodes (Gongylonema pulchrum, Parabronema pecariae, Texicospirura turki, and Physocephalus sexalatus) and one species of cestode (Moniezia sp.) comprised the helminth fauna of adult collared peccaries (Tayassu tajacu) from the plains in southern Texas. The community structure of the helminth fauna of peccaries from this region was basically dissimilar to that from the more humid Gulf coastal prairies of southern Texas in composition (by the conspicuous absence of certain species) and relative abundance of shared species. The distributions of each of the three common species of helminths (G. pulchrum, T. turki, and P. sexalatus) were overdispersed. The effects of selected habitat variables operating across host subpopulations (delineated by condition and sex) and of the extrinsic variable of season on the dispersion patterns of the three common species of helminths were examined. The hypothesis that heterogeneity within the host population, rather than across the collective host population, is the main factor generating overdispersion in natural parasite populations was not confirmed for the three common species of helminths. Overdispersion in P. sexalatus resulted from seasonal changes across the collective host population, with the greatest abundances occurring during the cool season. Aggregated abundances of G. pulchrum resulted from variation generated across host sex subpopulations, while the dispersion patterns of T. turki appeared to be unaffected by the habitat variables examined in this study.     

Helminths of white-bellied opossum from Brazil

Helminths were collected from 22 specimens of the white-bellied opossum (Didelphis albiventris) captured in the region of Pampulha (Belo Horizonte, Brazil), from May 1985 to March 1995. Ten species of helminths were collected; these included Rhopalias coronatus, Brachylaema migrans, Aspidodera raillieti, Cruzia tentaculata, Turgida turgida, Gongylonema sp., Viannaia hamata, Travassostrongylus orloffi, Trichuris didelphis and Capillaria sp.     

Poxvirus in scaled quail and prevalences of poxvirus-like lesions in northern bobwhites and scaled quail from Texas

Prevalences of poxvirus-like lesions were determined for 177 northern bobwhites (Colinus virginianus) and 24 scaled quail (Callipepla squamata) trapped in southern Texas from 1976 to 1979 and for 190 northern bobwhites and 105 scaled quail shot at five locations in southern Texas from 1980 to 1981. None of the northern bobwhites trapped in 1976-1977 was infected, but 54% of the trapped scaled quail were infected; 17% of the northern bobwhites and 34% of the scaled quail shot in 1980-1981 had pox lesions, primarily on the wings. Prevalence was unrelated to sex or age of birds. For both species, prevalence was greatest during late spring and early summer. Histologic and electron microscopic examination confirmed poxvirus in two scaled quail, which constituted the first report of poxvirus in this species.     

Effects of season and physical condition on the gastrointestinal helminth community of white-tailed deer from the Texas Edwards Plateau

Eighty-six adult female white-tailed deer, Odocoileus virginianus (Zimmermann), collected over a 12-mo period in the Texas Edwards Plateau, harbored six species of nematodes (Haemonchus contortus, Gongylonema pulchrum, Oesophagostomum venulosum, Ostertagia ostertagi, Cooperia sp., and Apteragia odocoilei), and two cestodes (Moniezia sp. and Taenia hydatigena). The patterns of distribution of the three common species of gastrointestinal helminths (H. contortus, O. venulosum, and G. pulchrum) were overdispersed. When analyzed for the main and interactive effects of the extrinsic and intrinsic variables of season and physical condition, respectively, aggregated abundances in H. contortus and O. venulosum appeared to result from the main effect of seasonal changes operating over the collective populations of these two species rather than from the intrinsic factor of physical condition operating within selected subpopulations. Abomasal parasite counts do not appear to be a useful index for monitoring herd condition of white-tailed deer from this geographic region.     

Helminths of California quail (Callipepla californica) and mountain quail (Oreortyx pictus) in western Oregon

Eighty California quail (Callipepla californica), collected from the E. E. Wilson Wildlife Area near Monmouth, Oregon (USA) during a 22 mo period, were examined for gastrointestinal helminths. Eight birds were infected with three species of nematodes, Heterakis isolonche, Dispharynx nasuta, and Capillaria sp., and two species of cestodes, Rhabdometra odiosa and Davainea sp. Except for D. nasuta, prevalence did not exceed 5% despite mesic conditions in the collection area. Two mountain quail (Oreortyx pictus) were collected from Lane County, Oregon (USA), near Blue River Reservoir; both were infected with the nematode Trichostrongylus tenuis.     

Helminths of sympatric striped, hog-nosed, and spotted skunks in west-central Texas

Twenty-eight hog-nosed skunks (Conepatus leuconotus), 23 striped skunks (Mephitis mephitis), and nine spotted skunks (Spilogale gracilis) from an area of sympatry in west-central Texas were examined for helminth parasites. Shared helminth species among all three host species were one nematode (Physaloptera maxillaris), two acanthocephalans (Pachysentis canicola, Macracanthorhynchus ingens), and one cestode (Mathevotaenia mephitis). Two nematodes (Gongylonema sp. and Filaria taxidaea) occurred in both the striped and hog-nosed skunks. One nematode (Filaroides milksi) and one acanthocephalan (Oncicola canis) were collected only from C. leuconotus. The most common helminth infections for striped and hog-nosed skunks were P. maxillaris and P. canicola. Helminth species richness was highest in hog-nosed skunks, but striped skunks had the highest prevalences and intensities of all the common helminth species. The helminth fauna of spotted skunks was markedly depauperate in terms of species richness and helminth abundance compared to the other two host species. Differences in helminth communities across these three sympatric skunks may be related to differences in their relative abundance, behavior, food habits, and geographic range.     

Helminthofauna of Opisthonema liberate and Harengula thrissina (Osteichthyes: Clupeidae) from Chamela Bay, Jalisco, Mexico

We collected helminths from the "sardines" Harengula thrissina (N = 61) and Opisthonema libertate (n = 43), from Chamela Bay, Jalisco State, Mexico (12 and six species, respectively). The nematode Pseudoterranova sp., reached the highest values of prevalence and mean abundance in O. libertate (11.6% and 0.13 worms per host, respectively), while in H. thrissina the digenean Parahemiurus merus reached a prevalence of 49.1% and a mean abundance of 1.40 worms per host. Low similarity values (qualitative and quantitative) between helminths of both host species is a result of their opportunistic feeding habits (100% of the parasitic species in H. thrissina and 66% of those from O. libertate infect their host from prey) and differential exposure to helminth larvae.     

Metazoan parasites of Himantopus mexicanus Muller (Aves) from southwestern Texas, with a checklist of helminth parasites from North America

Nineteen species of helminths were recovered from 34 of 35 black-necked stilts, Himantopus mexicanus Muller, collected from the Fort Bliss ponds, El Paso County, Texas. New host records are marked with an. The species identified were: Acoleus vaginatus, Davainea himantopodis, Diplophallus polymorphus, Eurycestus avoceti, Hymenolepis himantopodis, Hymenolepis sp. 1, Infula macrophallus, Coacitrema michiganensis, Cyclocoelum lanceolatum, Notocotylus sp., Parastrigea mexicanus, Tanaisia fedtschenkoi, Capillaria sp., C. anatis, C. contorta, C. mergi, Chevreuxia americana, Eustronglydes mergorum, and Splendidofilaria sp. Six species of mallophagan lice and 1 species of nasal mite, Rhinonyssus himantopus, were recovered. Helminths showed little concentration for dominance (0.09), were not very evenly distributed (0.49 +/- 0.08) nor very diverse (0.73 +/- 0.14), and most species were highly aggregated. The helminth community consisted of an unusually large number of core species (10). Three large species of tapeworms exhibited mostly paired infections, were mutually exclusive, and were negatively associated (-1).     

Helminth community composition, structure, and pattern in six dove species (Columbiformes: Columbidae) of South Texas

The helminth community composition and structure of 6 species of columbids residing in south Texas are reported and compared herein. Sixty individuals of the following species, rock pigeons (Columba livia [RP]), mourning doves (Zenaida macroura [MD]), Eurasian collared-doves (Streptopelia decaocto [ECD]), white-winged doves (Zenaida asiatica [WWD]), and common ground doves (Columbina passerina [CGD]), and 48 Inca doves (Columbina inca [ID]) were collected during the summer of 2006 and examined for helminths. Twelve helminth species were found (9 nematodes and 3 cestodes), representing 486 individuals. Nematodes numerically dominated the component community in all host species. Overall, helminth prevalence was similar among host sex within all dove species. However, prevalence of Skrjabinia bonini and Hymenolepis sp. in RPs was significantly different among host age groups (P = 0.01, P = 0.0002, respectively). Likewise, prevalence of Killigrewia delafondi was higher (P = 0.0001) in adult WWDs. Based on percent similarity and Jaccard's coefficient of community indices, helminth component communities were dissimilar, and the number of shared helminth species varied among host species. Data from this study suggest that the environment surrounding preferred host habitat and foraging strategies of each host species is the driving force behind helminth component communities. This study emphasizes the importance of examining co-occurring hosts at both local and regional scales to elucidate helminth community structure and patterns.     

Parasitic helminths of red-bellied woodpeckers (Melanerpes carolinus) from the Apalachicola National Forest in Florida

Seventy-four red-bellied woodpeckers (Melanerpes carolinus) from the Apalachicola National Forest (30 degrees 10'N, 84 degrees 40'W) in northwest Florida were examined for helminths. The most prevalent parasites were the nematode Aproctella stoddardi (11%) and the acanthocephalan Mediorhynchus centurorum (11%). New host records include Pseudaprocta samueli, A. stoddardi, Tridentocapillaria tridens, Diplotriaena americana, Dispharynx nasuta, Procyrnea pileata, Orthoskrjabinia rostellata, and Brachylaima fuscatum. The helminth fauna was characterized by low prevalences and intensities of infection and low numbers of species per bird (1.2). The frequency of prescribed burning and habitat understory flora composition did not influence the prevalences or intensities of helminths in red-bellied woodpeckers collected from 2 similar but differently managed sites within the forest.     

Spatial and temporal changes in prevalence of a cloacal cestode in wintering waterfowl along the Gulf Coast of Texas

The cloacal cestode Cloacotaenia megalops is one of the most common helminths of waterfowl. We investigated the effect of this parasite on the body condition of wintering waterfowl populations and compared prevalence among age-sex classes, over time and between habitat types on the upper Gulf Coast of Texas (USA) from October 1986-February 2000. Greater than 9,500 birds of 25 waterfowl species were examined for the parasite. There was no statistical difference (P > 0.05) in body condition between birds with and without the parasite. Average prevalence was lowest for geese (mean = 3.7%) versus 21 to 71% in duck species. Average prevalence was similar (P = 0.81) between diving ducks (mean = 46.9%) and puddle ducks (mean = 43.9%). Prevalence varied among age-sex classes and was related to sex rather than age. Variation among age-sex classes suggests differences in diet between sexes of duck species on the wintering grounds. There was no evidence for declining prevalence over the wintering period. Prevalence differed (P < 0.05) between collection sites, and thereby habitat types, for several species. Temporal trends indicate stable prevalence of C. megalops for diving ducks and increasing prevalence for puddle ducks. The increasing trend for puddle ducks may indicate declining habitat conditions resulting in increased exposure to the intermediate ostracod host.     

Helminth parasites of unisexual and bisexual whiptail lizards (Teiidae) in North America. I. The Colorado checkered whiptail (Cnemidophorus tesselatus)

Eleven of 27 (41%) parthenogenetic Colorado checkered whiptails (Cnemidophorus tesselatus) from four counties of western and southwestern Texas were infected with one or more helminths. These included a linstowiid cestode (Oochoristica sp.), a larval spirurid nematode (Physaloptera sp.) and two species of oxyurid nematodes (Parathelandros texanus and Pharyngodon warneri). This note, the first in a series of reports on helminths of Cnemidophorus spp., represents the first record of parasites from C. tesselatus.     

Non-native grasses reduce scaled quail habitat

Non-native grasses are frequently sown in the southwestern United States for livestock forage and erosion control. These grasses often spread from areas where they are planted and replace native grasses and forbs. We tested the hypothesis that chestnut-bellied scaled quail (Callipepla squamata castanogastris) avoid locations dominated by non-native grasses. We trapped scaled quail at 5 different sites in southern Texas, USA, and located quail fitted with necklace-style transmitters 3 times/week during 2013–2014. We manually delineated plant communities using aerial maps and on-the-ground knowledge of the study sites. We examined second-order (home-range scale) selection by comparing proportion of the areas of plant communities within 62 scaled quail home ranges (used) paired with random home ranges (available). We examined third-order (within-home-range scale) selection by comparing the composition of bird location (used) and random (available) points based on proportion of points within plant communities. For both home-range scale and within-home-range scale analyses, we used non-parametric multivariate analysis of variance with 9,999 random permutations. We examined fourth-order (organism-centered) selection by measuring vegetation variables at used and available locations and then estimating the relative probability of use of vegetation variables and by estimating continuous selection functions for variables that were influential in determining relative probability of use. Buffelgrass (Pennisetum ciliare) and Old World bluestems (Bothriochloa spp., Dichanthium annulatum and other Dichanthium spp.) comprised 99% (95% CI = 98–100%, n = 143 sites where non-native plants occurred) of the non-native grasses in our study areas. Scaled quail avoided non-native and riparian plant communities at the home-range and within-home-range scales of selection. At the organism-centered scale of selection, odds of use by scaled quail decreased 28% for every 10% increase in non-native grass cover and increased 12% for every 10% increase in shrub canopy cover. Scaled quail avoided locations with >10% canopy cover of non-native grasses. Based on avoidance at 3 scales of selection, dominance of buffelgrass and Old World bluestems degrades habitat for scaled quail. Spread and sowing of non-native grasses and brush clearing may be partly responsible for declines in scaled quail populations. © 2019 The Wildlife Society.     

Evidence for Regionally Synchronized Cycles in Texas Quail Population Dynamics

Abstract: Knowledge of the possible role of cyclic behavior in wildlife dynamics assists in understanding and managing populations. Using spectrum, we analyzed time series (1978-2002) on the abundance of northern bobwhites (Colinus virginianus) and scaled quail (Callipepla squamata) in several ecological regions in Texas, USA, to test for the presence of cycles; we also tested whether drought severity (Modified Palmer Drought Severity Index) exhibited cyclic dynamics and whether quail and drought cycles were synchronized among regions. We found evidence of population cyclicity in all ecoregions we tested (5 for bobwhites, 4 for scaled quail) based on both Texas Parks and Wildlife and North American Breeding Bird Survey count data. Periods of the observed cycles generally were 5-6 years (bobwhites) or 2-3 years (scaled quail), depending on ecoregion and data source. Cyclicity was most pronounced for bobwhites in the Rolling Plains (north TX) and the South Texas Plains. The Palmer Index exhibited a roughly 5-year cycle in 5 of 6 regions we tested. A 5-year bobwhite and Palmer Index cycle were synchronous in 3 contiguous ecoregions totaling 27,200,000 ha. Wet-dry cycles seemed to synchronize bobwhite cycles in Texas. Our results suggest that habitat manipulations aimed at improving habitat conditions during dry periods, such as reducing livestock stocking rates, could provide ground cover similar to that available in wet periods.     

Visceral helminth communities of an insular population of feral swine

Nine species of helminths, all nematodes, were recovered from the viscera of 48 feral swine (Sus scrofa) from Cumberland Island, Georgia. Both the overdispersed frequency distributions and the abundances of the four common species of helminths (Stephanurus dentatus, Metastrongylus apri, M. pudendotectus and Gongylonema pulchrum) did not vary significantly across the main and interactive effects of host sex and/or seasons. Whether or not the present low population densities of feral swine on Cumberland Island has influenced the pattern of fluctuations in abundances of helminth species across seasons as often observed in helminth communities from other hosts was not resolved. The apparent recent decline in prevalences and abundances, and the loss of certain species from the helminth communities of feral swine on the island may be explained partially by the decreasing transmission potentials of direct life cycle species caused by a recent marked reduction of numbers of individuals in the host population. Conversely, the apparent increased prevalence and abundance of three species of helminths (S. dentatus, M. apri and M. pudendotectus) may be related to their common utilization of earthworms as paratenic or intermediate hosts. Gongylonema pulchrum was the only helminth in which abundances seemed to remain unchanged. This was the only species that was not strictly host specific to feral swine. We found no evidence that helminth infections were responsible for morbidity or mortality in this feral swine population.     

Influence of habitat modification on the community of gastrointestinal helminths of cotton rats.

Dynamics of communities of gastrointestinal helminths of cotton rats (Sigmodon hispidus) were monitored in response to five experimental brush management treatments using herbicide applications with and without prescribed burning on the Cross Timbers Experimental Range in Payne County, Oklahoma (USA). A total of 113 adult cotton rats (68 male and 45 female) was collected from experimental pastures in winter and summer 1986 resulting in the recovery of five species of helminths: Longistriata adunca, Syphacia sigmodontis, Strongyloides sp., Protospirura muris, and Raillietina sp. Prevalences of Raillietina sp. and S. sigmodontis were greater on control than herbicide-treated pastures. Prevalence and abundance of Raillietina sp. and prevalence of S. sigmodontis were significantly lower on annually burned, herbicide-treated pastures compared to unburned herbicide-treated pastures. Triclopyr-treated pastures had greater abundances of L. adunca and lower abundances of Raillietina sp. than those treated with tebuthiuron. Abundances of L. adunca also decreased from winter to summer on annually burned, herbicide-treated pastures while increasing on other pastures. Distribution of all helminths was overdispersed, but distribution of L. adunca showed a significant brush treatment by season interaction as a result of greater overdispersion in summer than winter for cotton rats inhabiting brush-treated pastures. Our results indicate that man-induced habitat modifications can alter host-parasite relationships in the community.     

Studies on endoparasites of the black bear (Ursus americanus) in the southeastern United States.

Examination of 53 black bears (Ursus americanus) from six states in the southeastern United States revealed at least 17 species of endoparasites, including Sarcocystis sp., Spirometra mansonoides (spargana), Macracanthorhynchus ingens, Ancylostoma caninum, Arthrocephalus lotoris, Baylisascaris transfuga, Capillaria aerophila, Capillaria putorii, Crenosoma sp., Cyathospirura sp., Dirofilaria immitis, Gnathostoma sp., Gongylonema pulchrum, microfilariae, Molineus barbatus, Physaloptera sp. and Strongyloides sp. Twelve of these represent new host records for black bear, and two are considered to be new species. Data are presented on prevalence, intensity and geographic distribution of each species. Pathologic effects were associated with infections of spargana of S. mansonoides and adults of C. aerophilia.     

Longer holding times decrease dispersal but increase mortality of translocated scaled quail

Scaled quail (Callipepla squamata) decline caused by habitat loss and fragmentation increased interest in translocation to reestablish populations. Yet factors determining translocation success are poorly understood. We tested hypotheses concerning the influence of source population and variation in delayed release strategy (1–9 weeks) on mortality and dispersal of wild-caught, translocated scaled quail. We trapped and translocated quail from 2016–2017 from source populations in the Edwards Plateau and Rolling Plains ecoregions to a large contiguous (>40,000 ha) release site in Knox County, Texas, USA. We evaluated mortality and dispersal of translocated females as a function of source population, holding time prior to release, age, release location, and year using a multi-state mark-recapture model with state uncertainty. Scaled quail translocated within the Rolling Plains were more likely to exhibit philopatry to the release site. Quail with longer holding times had higher mortality but lower dispersal rates. The Edwards Plateau is a suitable source site for translocation in the Rolling Plains. The reduced dispersal but higher mortality of translocated scaled quail associated with longer holding times creates a decision tradeoff for managers.     

Gastrointestinal parasites of the colobus monkeys of Uganda

From August 1997 to July 2003, we collected 2,103 fecal samples from free-ranging individuals of the 3 colobus monkey species of Uganda-the endangered red colobus (Piliocolobus tephrosceles), the eastern black-and-white colobus (Colobus guereza), and the Angolan black-and-white colobus (C. angolensis)--to identify and determine the prevalence of gastrointestinal parasites. Helminth eggs, larvae, and protozoan cysts were isolated by sodium nitrate flotation and fecal sedimentation. Coprocultures facilitated identification of helminths. Seven nematodes (Strongyloides fulleborni, S. stercoralis, Oesophagostomum sp., an unidentified strongyle, Trichuris sp., Ascaris sp., and Colobenterobius sp.), 1 cestode (Bertiella sp.), 1 trematode (Dicrocoeliidae), and 3 protozoans (Entamoeba coli, E. histolytica, and Giardia lamblia) were detected. Seasonal patterns of infection were not apparent for any parasite species infecting colobus monkeys. Prevalence of S. fulleborni was higher in adult male compared to adult female red colobus, but prevalence did not differ for any other shared parasite species between age and sex classes.