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Jeffrey E. Lovich

Publications and source records attributed to Jeffrey E. Lovich.

At least 91 records · Page 5Linked to original sources
USGS2015

Using motion-sensor camera technology to infer seasonal activity and thermal niche of the desert tortoise ( Gopherus agassizii )

Understanding the relationships between environmental variables and wildlife activity is an important part of effective management. The desert tortoise ( Gopherus agassizii ), an imperiled species of arid environments in the southwest US, may have increasingly restricted windows for activity due to current warming trends. In summer 2013, we deployed 48 motion sensor cameras at the entrances of tortoise burrows to investigate the effects of temperature, sex, and day of the year on the activity of desert tortoises. Using generalized estimating equations, we found that the relative probability of activity was associated with temperature (linear and quadratic), sex, and day of the year. Sex effects showed that male tortoises are generally more active than female tortoises. Temperature had a quadratic effect, indicating that tortoise activity was heightened at a range of temperatures. In addition, we found significant support for interactions between sex and day of the year, and sex and temperature as predictors of the probability of activity. Using our models, we were able to estimate air temperatures and times (days and hours) that were associated with maximum activity during the study. Because tortoise activity is constrained by environmental conditions such as temperature, it is increasingly vital to conduct studies on how tortoises vary their activity throughout the Sonoran Desert to better understand the effects of a changing climate.

California↗
USGS2015

The effect of research activities and winter precipitation on voiding behaviour of Agassiz’s desert tortoises ( Gopherus agassizii )

Context: There is little information available on how research activities might cause stress responses in wildlife, especially responses of threatened species such as the desert tortoise ( Gopherus agassizii ). Aims: The present study aims to detect behavioural effects of researcher handling and winter precipitation on a natural population of desert tortoises in the desert of Southwestern United States, over the period 1997 to 2014, through extensive assessments of capture events during multiple research studies, and capture–mark–recapture survivorship analysis. Methods: Juvenile and adult desert tortoises were repeatedly handled with consistent methodology across 18 years during 10 study seasons. Using a generalised linear mixed-effects model, we assessed the effects of both research manipulation and abiotic conditions on probability of voiding. Additionally, we used a Cormack–Jolly–Seber model to assess the effects of winter precipitation and voiding on long-term apparent survivorship. Key results: Of 1008 total capture events, voiding was recorded on 83 (8.2%) occasions in 42 different individuals. Our top models indicated that increases in handling time led to significantly higher probabilities of voiding for juveniles, females and males. Similarly, increases in precipitation resulted in significantly higher probabilities of voiding for juveniles and females, but not for males. Tortoise capture frequency was negatively correlated with voiding occurrence. Cormack–Jolly–Seber models demonstrated a weak effect of winter precipitation on survivorship, but a negligible effect for both voiding behaviour and sex. Conclusions: Handling-induced voiding by desert tortoises may occur during common research activities and years of above average winter precipitation. Increased likelihood of voiding in individuals with relatively low numbers of recaptures suggested that tortoises may have perceived researchers initially as predators, and therefore voided as a defensive strategy. Voiding does not appear to impact long-term survivorship in desert tortoises at this site. Implications: This study has demonstrated that common handling practices on desert tortoise may cause voiding behaviour. These results suggest that in order to minimise undesirable behavioural responses in studied desert tortoise populations, defined procedures or protocols must be followed by the investigators to reduce contact period to the extent feasible.

Wildlife Research↗
USGS2015

Nelson's big horn sheep ( Ovis canadensis nelsoni ) trample Agassiz's desert tortoise ( Gopherus agassizii ) burrow at a California wind energy facility

Research on interactions between Agassiz's desert tortoises ( Gopherus agassizii ) and ungulates has focused exclusively on the effects of livestock grazing on tortoises and their habitat (Oldemeyer, 1994). For example, during a 1980 study in San Bernardino County, California, 164 desert tortoise burrows were assessed for vulnerability to trampling by domestic sheep ( Ovis aries ). Herds of grazing sheep damaged 10% and destroyed 4% of the burrows (Nicholson and Humphreys 1981). In addition, a juvenile desert tortoise was trapped and an adult male was blocked from entering a burrow due to trampling by domestic sheep. Another study found that domestic cattle ( Bos taurus ) trampled active desert tortoise burrows and vegetation surrounding burrows (Avery and Neibergs 1997). Trampling also has negative impacts on diversity of vegetation and intershrub soil crusts in the desert southwest (Webb and Stielstra 1979). Trampling of important food plants and overgrazing has the potential to create competition between desert tortoises and domestic livestock (Berry 1978; Coombs 1979; Webb and Stielstra 1979).

Bulletin of the Southern California Academy of Sci↗
USGS2015

Golden Eagle mortality at a utility-scale wind energy facility near Palm Springs, California

Golden Eagle ( Aquila chrysaetos ) mortality associated with wind energy turbines and infrastructure is under-reported and weakly substantiated in the published literature. I report two cases of mortality at a utility-scale renewable energy facility near Palm Springs, California. The facility has been in operation since 1984 and included 460 65KW turbines mounted on 24.4 m or 42.7 m lattice-style towers with 8 m rotor diameters. One mortality event involved a juvenile eagle that was struck and killed by a spinning turbine blade on 31 August, 1995. The tower was 24.4 m high. The other involved an immature female that was struck by a spinning blade on another 24.4 m tower on 17 April, 1997 and was later euthanized due to the extent of internal injuries. Other raptor mortalities incidentally observed at the site, and likely attributable to turbines, included three Red-tailed Hawks ( Buteo jamaicensis ) found near turbines.

California↗
USGS2015

Comment on Spracklandus Hoser, 2009 (Reptilia, Serpentes, ELAPIDAE): request for confirmation of availability of the generic name and for the nomenclatural validation of the journal in which it was published (Case 3601; BZN 70:234–237; 71:30–38; 133-135,181-182 ,252-253)

In Case 3601 Raymond Hoser has asked the Commission to validate for the purposes of nomenclature the name Spracklandus Hoser, 2009, and ‘the journal in which it was published,’ issue 7 of the Australasian Journal of Herpetology (AJH). We note that the entire run of AJH has been written, edited, and published solely by Hoser. Although his requests to the Commission were presented as narrow and, in his words, ‘routine matters,’ we are convinced that they represent an important tipping-point with broad implications of major concern for zoological taxonomy and nomenclature as a whole and, by extension, the greater scientific community. Since Hoser’s actions and works have failed to follow scientific best practices (e.g. Turtle Taxonomy Working Group, 2007, 2014; Kaiser et al., 2013; Kaiser, 2014) and both the Commission’s general Recommendations and Code of Ethics in Appendix A, the global herpetological community has widely rejected his taxonomic decisions and resultant nomenclature. This has unfortunately caused a confusing dual nomenclature to develop in the herpetological community, with most boycotting or ignoring Hoser’s 700+ new names coined in the AJH, while he and a few personal followers actively promote their usage. We believe that suppression of the name Spracklandus , and all issues of AJH, is the only effective way to bring this contentious and confusing issue to resolution. The plenary power available under Article 81.1 of the Code exist specifically to allow the Commission to make rulings in individual cases that disturb stability and cause confusion, whether the works are Code-compliant or not. We maintain that it is in the interest of nomenclatural stability, not only for herpetology, but for all of zoological taxonomy, that the plenary power be invoked to declare the works in AJH unavailable, regardless of any narrow interpretation of their technical Code-compliance. We present our arguments for rejection of the validity of AJH in the following commentary. In view of the wide-reaching implications of this case for all of zoology, and reflecting the deep and broad-based community concern over these issues, our contributing authors include 70 global scientific leaders and accomplished amateurs from a wide variety of zoological disciplines.

Bulletin of Zoological Nomenclature↗
USGS2015

Interanal seam loss in Asian turtles of the Cuora flavomarginata complex (Testudines, Geoemydidae)

The taxonomy of Asian box turtles of the genus Cuora is complicated by the description of numerous valid and invalid taxa over the last several decades. However, some characteristics used to differentiate species are questionable. Members of the C. flavomarginata complex are defined by some, but not all, taxonomists as having reduced interanal seam lengths relative to other species. We examined the ratio of interanal scute seam length divided by midline anal scute length in C. flavomarginata and C. evelynae. Hatchlings show a seam that divides 100% of the anal scute along the midline. As individuals increase in carapace length, there is a tendency for the percentage to decrease, especially in females, although there is considerable overlap. We suggest that the decrease in interanal seam length is due to abrasion of the plastron on the substrate as turtles grow larger and older. Differences in habitat substrates across the range of the species may contribute to the wide variation we observed.

Herpetological Bulletin↗
USGS2015

Nest-site characteristics of Glyptemys muhlenbergii (Bog Turtle) in New Jersey and Pennsylvania

Nest-site selection can affect both the survival and fitness of female turtles and their offspring. In many turtle species, the nest environment determines the thermal regime during incubation, length of incubation period, sex ratio of the hatchlings, and exposure to predators and other forms of mortality for both mothers and their offspring. Between 1974 and 2012, we collected detailed data on habitat variables at 66 Glyptemys muhlenbergii (Bog Turtle) nests in 9 different bogs, fens, and wetland complexes in New Jersey and Pennsylvania. The nests had a mean elevation above the substrate of 8.2 cm, and many were shallow and located in raised tussocks of grass or sedges. Females covered most nests, but we also observed partially or completely uncovered eggs. Some females deposited eggs in communal nests; we found 4 nests with 2 separate clutches, and 2 nests with 3 clutches. Principal component analysis confirmed the importance of cover and vegetation to nest-site selection in this species. Availability of open, shade-free, wet nesting areas is an important habitat requirement for Bog Turtles.

New Jersey, Pennsylvania↗
USGS2015

Gopherus Agassizii (Agassiz’s Desert Tortoise). Mechanical Injury

On 3 June 2015 at 1024 h, a team of U.S. Geological Survey scientists located an immature Gopherus agassizii (Agassiz’s desert tortoise) at Joshua Tree National Park, near the southern Cottonwood Canyon entrance. The habitat in the area is typical of the Sonoran Desert in that part of California with various trees and shrubs including Larrea tridentate (creosote bush), Parkinsonia florida (blue palo verde), Olneya tesota (ironwood), Fouquieria splendens (ocotillo) and Psorothamnus spinosus (smoketree), as well as numerous species of cacti, herbaceous plants and shrubs. The 89.4 mm in carapace length G. agassizii was estimated to be four years old by counting growth rings on the plastron, and weighed 160g. It was found basking on a flat spot on a north-facing, steep, rocky slope with a Ferocactus cylindraceus (California barrel cactus) spine impaling the G. agassizii under the right leg.

California↗
USGS2014

Does the timing of attainment of maturity influence sexual size dimorphism and adult sex ratio in turtles?

The attainment of sexual maturity has been shown to affect measures of sexual size dimorphism (SSD) and adult sex ratios in several groups of vertebrates. Using data for turtles, we tested the model that sex ratios are expected to be male-biased when females are larger than males and female-biased when males are larger than females because of the relationship of each with the attainment of maturity. Our model is based on the premise that the earlier-maturing sex remains smaller, on average throughout life, and predominates numerically unless the sexes are strongly affected by differential mortality, differential emigration, and immigration, or biased primary sex ratios. Based on data for 24 species in seven families, SSD and sex ratios were significantly negatively correlated for most analyses, even after the effect of phylogenetic bias was removed. The analyses provide support for the model that SSD and adult sex ratios are correlated in turtles as a result of simultaneous correlation of each with sexual differences in attainment of maturity (bimaturism). Environmental sex determination provides a possible mechanism for the phenomenon in turtles and some other organisms.

Biological Journal of the Linnean Society↗
USGS2014

Clinal variation or validation of a subspecies? A case study of the Graptemys nigrinoda complex (Testudines: Emydidae)

Widely distributed species often display intraspecific morphological variation due to the abiotic and biotic gradients experienced across their ranges. Historically, in many vertebrate taxa, such as birds and reptiles, these morphological differences within a species were used to delimit subspecies. Graptemys nigrinoda is an aquatic turtle species endemic to the Mobile Bay Basin. Colour pattern and morphological variability were used to describe a subspecies ( G. n. delticola ) from the lower reaches of the system, although it and the nominate subspecies also reportedly intergrade over a large portion of the range. Other researchers have suggested that these morphological differences merely reflect clinal variation. Our molecular data (mtDNA) did not support the existence of the subspecies, as the haplotypes were differentiated by only a few base pairs and one haplotype was shared between the putative subspecies. While there were significant morphological and pattern differences among putative specimens of G. n. nigrinoda, G. n. delticola and G. n. nigrinoda × delticola , these differences probably represent clinal variation as they were also related to environmental variables [i.e. cumulative drainage area and drainage (categorical)]. Specimens occupying slow-current, high-turbidity river reaches (e.g. the Tensaw River) exhibited greater relative carapace heights and more dark pigmentation, while specimens occupying fast-current, clearer rivers (e.g. the upper Alabama, Cahaba and Tallapoosa rivers) exhibited lower carapace heights and more yellow pigmentation. Given the absence of clear molecular and morphological differences that are related to drainage characteristics, we suggest that there is not sufficient evidence for the recognition of G. n. delticola as a distinct subspecies.

Alabama;Mississippi↗
USGS2014

Graptemys pulchra Baur 1893: Alabama Map Turtle

The Alabama Map Turtle, Graptemys pulchra (Family Emydidae), is a moderately large riverine species endemic to the Mobile Bay drainage system of Alabama, Georgia, and Mississippi. Sexual size dimorphism is pronounced, with adult females (carapace length [CL] to 273 mm) attaining more than twice the size of adult males (CL to 117 mm). The species is an inhabitant of relatively large, swift creeks and rivers, often with wide sandbars. Stream sections open to the sun and with abundant basking sites in the form of logs and brush are preferred. Six to seven clutches of 4–7 eggs are laid each year on river sandbars. Although the species is locally abundant, populations are threatened by habitat destruction, declines in their prey base, commercial collection, and vandalism. It is listed as a Species of Special Concern in Alabama.

Alabama;Georgia;Mississippi↗
USGS2014

Climatic variation and tortoise survival: has a desert species met its match?

While demographic changes in short-lived species may be observed relatively quickly in response to climate changes, measuring population responses of long-lived species requires long-term studies that are not always available. We analyzed data from a population of threatened Agassiz’s desert tortoises (Gopherus agassizii) at a 2.59 km 2 study plot in the Sonoran Desert ecosystem of Joshua Tree National Park, California, USA from 1978 to 2012 to examine variation in apparent survival and demography in this long-lived species. Transect-based, mark-recapture surveys were conducted in 10 of those years to locate living and dead tortoises. Previous modeling suggested that this area would become unsuitable as tortoise habitat under a warming and drying climate scenario. Estimated adult population size declined greatly from 1996 to 2012. The population appeared to have high apparent survival from 1978 to 1996 but apparent survival decreased from 1997 to 2002, concurrent with persistent drought. The best model relating apparent survivorship of tortoises ≥18 cm over time was based on a three year moving average of estimated winter precipitation. The postures and positions of a majority of dead tortoises found in 2012 were consistent with death by dehydration and starvation. Some live and many dead tortoises found in 2012 showed signs of predation or scavenging by mammalian carnivores. Coyote (Canis latrans) scats and other evidence from the site confirmed their role as tortoise predators and scavengers. Predation rates may be exacerbated by drought if carnivores switch from preferred mammalian prey to tortoises during dry years. Climate modeling suggests that the region will be subjected to even longer duration droughts in the future and that the plot may become unsuitable for continued tortoise survival. Our results showing wide fluctuations in apparent survival and decreasing tortoise density over time may be early signals of that possible outcome.

California↗
USGS2014

Traditional cultural use as a tool for inferring biogeography and provenance: a case study involving painted turtles ( Chrysemys picta ) and Hopi Native American culture in Arizona, USA

Inferring the natural distribution and native status of organisms is complicated by the role of ancient and modern humans in utilization and translocation. Archaeological data and traditional cultural use provide tools for resolving these issues. Although the painted turtle (Chrysemys picta) has a transcontinental range in the United States, populations in the Desert Southwest are scattered and isolated. This pattern may be related to the fragmentation of a more continuous distribution as a result of climate change after the Pleistocene, or translocation by Native Americans who used turtles for food and ceremonial purposes. Because of these conflicting or potentially confounded possibilities, the distribution and status of C. picta as a native species in the state of Arizona has been questioned in the herpetological literature. We present evidence of a population that once occurred in the vicinity of Winslow, Arizona, far from current remnant populations on the upper Little Colorado River. Members of the Native American Hopi tribe are known to have hunted turtles for ceremonial purposes in this area as far back as AD 1290 and possibly earlier. Remains of C. picta are known from several pueblos in the vicinity including Homol'ovi, Awatovi, and Walpi. Given the great age of records for C. picta in Arizona and the concordance of its fragmented and isolated distribution with other reptiles in the region, we conclude that painted turtles are part of the native fauna of Arizona.

Arizona;Utah↗
USGS2014

Hybridization of two megacephalic map turtles (testudines: emydidae: Graptemys ) in the Choctawhatchee River drainage of Alabama and Florida

Map turtles of the genus Graptemys are highly aquatic and rarely undergo terrestrial movements, and limited dispersal among drainages has been hypothesized to drive drainage-specific endemism and high species richness of this group in the southeastern United States. Until recently, two members of the megacephalic “ pulchra clade,” Graptemys barbouri and Graptemys ernsti , were presumed to be allopatric with a gap in both species' ranges in the Choctawhatchee River drainage. In this paper, we analyzed variation in morphology (head and shell patterns) and genetics (mitochondrial DNA and microsatellite loci) from G. barbouri , G. ernsti , and Graptemys sp. collected from the Choctawhatchee River drainage, and we document the syntopic occurrence of those species and back-crossed individuals of mixed ancestry in the Choctawhatchee River drainage. Our results provide a first counter-example to the pattern of drainage-specific endemism in megacephalic Graptemys . Geologic events associated with Pliocene and Pleistocene sea level fluctuations and the existence of paleo-river systems appear to have allowed the invasion of the Choctawhatchee system by these species, and the subsequent introgression likely predates any potential human-mediated introduction.

Alabama, Florida↗
USGS2014

A 21-year study of seasonal and interspecific variation of hatchling emergence in a nearctic freshwater turtle community: to overwinter or not to overwinter?

Hatchling emergence patterns were studied in a community of six species of freshwater turtles in Lancaster County, Pennsylvania, U.S.A. including: Chelydra serpentina, Chrysemys picta, Clemmys guttata, Glyptemys insculpta, G. muhlenbergii , and Sternotherus odoratus . Data were collected every year from 1965 to 1985 on estimated date of emergence, carapace length, April – May precipitation, August – September precipitation, annual precipitation, and low temperature and occurrence of precipitation during the 24-hrs prior to the time of each hatchling detection (n = 806). Chelydra serpentina, Ch. picta , and Cl. guttata hatchlings have a facultative delayed emergence strategy. The other species ( G. insculpta, G. muhlenbergii , and S. odoratus ) appear to be obligate early emergers, with the exception of one hatchling G. muhlenbergii that delayed emergence. Early emergence occurred in some species every year except 1973, the year following intense flooding and nest destruction associated with a major hurricane. However, the majority of hatchlings delayed emergence until the year following oviposition. Mean estimated calendar day of emergence varied annually in C. serpentina and Ch. picta . The same variable also varied among species for comparisons of both early and delayed emergence. Chelydra serpentina hatchlings emerged earlier than all other species whether they used an early or delayed strategy. Carapace length of Ch. picta hatchlings varied significantly among years and C. serpentina hatchlings that delayed emergence were significantly larger in carapace length than those that emerged early. Seasonal and previous 24-hr precipitation had varying effects on the number of emerging hatchlings, but August – September precipitation in one year had a strong correlation with the number of hatchlings that delayed emergence until the following spring. The number of hatchlings detected peaked at a previous 24-hour air temperature of about 12°C for both early and late emergence. Small species like G. muhlenbergii and S. odoratus may emerge early to limit potential hatchling competition in diverse communities of freshwater turtles with primarily delayed emergence.

Herpetological Monographs↗
USGS2014

Nest site characteristics, nesting movements, and lack of long-term nest site fidelity in Agassiz's desert tortoises at a wind energy facility in southern California

Nest site selection has important consequences for maternal and offspring survival and fitness. Females of some species return to the same nesting areas year after year. We studied nest site characteristics, fidelity, and daily pre-nesting movements in a population of Agassiz’s desert tortoises (Gopherus agassizii) at a wind energy facility in southern California during two field seasons separated by over a decade. No females returned to the same exact nest site within or between years but several nested in the same general area. However, distances between first and second clutches within a year (2000) were not significantly different from distances between nests among years (2000 and 2011) for a small sample of females, suggesting some degree of fidelity within their normal activity areas. Environmental attributes of nest sites did not differ significantly among females but did among years due largely to changes in perennial plant structure as a result of multiple fires. Daily pre-nesting distances moved by females decreased consistently from the time shelled eggs were first visible in X-radiographs until oviposition, again suggesting some degree of nest site selection. Tortoises appear to select nest sites that are within their long-term activity areas, inside the climate-moderated confines of one of their self-constructed burrows, and specifically, at a depth in the burrow that minimizes exposure of eggs and embryos to lethal incubation temperatures. Nesting in “climate-controlled” burrows and nest guarding by females relaxes some of the constraints that drive nest site selection in other oviparous species.

California↗