Perspectives on Iowa\u27s Declining Amphibians and Reptiles

Changes in range and abundance of Iowa\u27s amphibians and reptiles can be deduced by comparing records from recent studies with excellent collections from Iowa by Professor R. M. Bailey made from 1938-1943 in addition to museum records accumulated before 1950. Additional recent data make necessary this updating of a similar study conducted in 1980. The current study finds many of our frogs to be in decline, some in a pattern from north to south, but most as a diffused loss of populations, probably as a result of habitat destruction. The crawfish frog, one of the two frogs considered threatened in 1981, may be extirpated; the other, the spring peeper, is moderately abundant. This reevaluation finds the smallmouth salamander, and tiger salamander to be maintaining populations where the habitat is undisturbed, but survival of Iowa\u27s other three salamanders is precarious. The turtles appear consistent with the 1981 study except for the red-eared slider, now known to be common in southeastern Iowa. There is no change in the analysis of Iowa\u27s lizards, all of which are declining; the survival of two is tenuous. Two snakes believed to be rare in 1981, the smooth earth snake, and the northern redbelly snake, are now known to be common in parts of the state. All of the venomous snakes are clearly less abundant than in 1981, although the timber rattlesnake has declined less than the others. The current analysis finds strong evidence for severe decline of our largest diurnal snake species, especially the bullsnake, and suggests that even though often considered common, their long-term survival is threatened

The Distribution and Variation of the Western Earth Snake, Virginia valeriae elegans (Kennicott) in Iowa

Western earth snakes, Virginia valeriae elegans, were known in Iowa from only three specimens and considered very rare until the present study. Intense effort to find them in the last two years produced specimens from only the lower Des Moines and Chariton River drainages. The snakes were found to be closely associated with timbered, rocky terrain near streams and to be potentially endangered where timber is permanently removed. Sampling showed two geographic areas in the Des Moines River drainage inhabited by this snake; specimens from the two areas were very similar morphologically. Iowa specimens usually lack the light vertebral stripe characteristic of the species in most of its range and have small, dark spots on the head and neck. Meristic variation is slight

Observations of MMOD Impact Damage to the ISS

This paper describes meteoroid and orbital debris (MMOD) damage observations on the International Space Station (ISS). Several hundred MMOD damage sites on ISS have been documented using imagery taken from ISS windows. MMOD damage sites visible from ISS windows are typically larger approximately 5mm diameter and greater due to the larger viewer-to-surface distance. Closer inspection of these surfaces by astronauts during spacewalks reveals many smaller features that are typically less distinct. Characterization of these features as MMOD or non- MMOD is difficult, but can be partially accomplished by matching physical characteristics of the damage against typical MMOD impact damage observed on ground-based impact tests. Numerous pieces of space-exposed ISS hardware were returned during space shuttle missions. Subsequent ground inspection of this hardware has also contributed to the database of ISS MMOD impact damage. A handful of orbital replacement units (ORUs) from the ISS active thermal control and electrical power subsystems were swapped out and returned during the Space Shuttle program. In addition, a reusable logistics module was deployed on ISS for a total 59.4 days on 11 shuttle missions between 2001 and 2011 and then brought back in the shuttle payload bay. All of this returned hardware was subjected to detailed post-flight inspections for MMOD damage, and a database with over 1,400 impact records has been collected. A description of the largest observed damage features is provided in the paper. In addition, a discussion of significant MMOD impact sites with operational or design aspects is presented. MMOD impact damage to the following ISS modules/subsystems is described: (1) Solar Arrays, (2) US and Russian windows, (3) Extravehicular Activity (EVA) handrails, (4) Radiators, and (5) Russian Functional Cargo Block (FGB) module

Comparison of Risk from Orbital Debris and Meteoroid Environment Models on the Extravehicular Mobility Unit (EMU)

A well-known hazard associated with exposure to the space environment is the risk of failure from an impact from a meteoroid and orbital debris (MMOD) particle. An extravehicular mobility unit (EMU) spacesuit impact during a US extravehicular activity (EVA) is of great concern as a large leak could prevent an astronaut from safely reaching the airlock in time resulting in a loss of life. A risk assessment is provided to the EVA office at the Johnson Space Center (JSC) by the Hypervelocity Impact Technology (HVIT) group prior to certification of readiness for each US EVA. Need to understand the effect of updated meteoroid and orbital debris environment models to EMU risk

A Relationship Between River Modification and Species Richness of Freshwater Turtles in Iowa

Comparisons were made of turtle populations in Red Rock Reservoir and the major rivers of the Mississippi River and Missouri River damage systems in Iowa. Of the inland rivers of the Mississippi drainage examined in this study, the Des Moines River had the least amount of remaining turtle habitat. Number of turtle species ranged from five in the Des Moines River to 11 in the Mississippi River, but only three species were found in Red Rock Reservoir. In the Missouri drainage, number of turtle species ranged from three in both the Little Sioux and Nishnabotna rivers to five in the Missouri River. Regression analysis found remaining turtle habitat to be the strongest predictor of species richness. Stream modification appeared to lower the species richness of riverine turtles by eliminating intolerant species. Intolerant forms were absent when river modification eliminated their habitat and created a more uniform and simplified environment Map turtles (Graptemys geographica LeSueur), false map turtles (Graptemys pseudogeographica Gray), Blanding\u27s turtles (Emydotdea blandingi Holbrook), and smooth soft-shells (Apalone mutica LeSueur), appeared to be most affected by modification. Turtle species richness was lower in Red Rock Reservoir than in the Des Moines River, possibly due to the great fluctuation in the water level of the reservoir

The Relationship Between Pond Bottom Type and Growth Rate of Western Painted Turtles Chrysemys picta belli in Iowa, a Preliminary Report

Several populations of western painted turtles (Chrysemys picta belli) were sampled during 1970 to determine the possible relationship between turtle growth rate and type of pond substrate. The populations sampled were selected because they existed in lentic habitats that had either highly organic, mud substrates or relatively inorganic, sand substrates. Age determinations based on plastral annuli showed turtles from highly organic substrates to grow more rapidly than those from substrates with less apparent organic matter. Females attained greater size than males in both habitat extremes

A Key to the Eggs and Nests of Iowa Turtles

Biologists often need to identify destroyed turtle nests where a predator has excavated and eaten the eggs. We present a dichotomous key to the eggs and nests of Iowa\u27s turtles based on egg or nest morphology and known range of the species. Egg and nest morphology clearly separated most nests of the families Chelydridae and Kinosternidae and many of the Emydidae. However, egg morphology must be combined with known range to distinguish wood turtles (Glyptemys insculpta) from other emydids. These factors will also separate most false map turtles (Graptemys pseudogeographica) from other species. Similarities among egg morphologies, nest morphologies, and ranges make the map turtles (Graptemys spp.) and red-eared sliders (Trachemys scripta) difficult to separate in southeastern Iowa

The Early History and Recent Trends in Iowa Herpetology

Herpetological exploration of Iowa began in 1823 with Long\u27s expedition to the Rocky Mountains. From that time until an 1892 publication by Osborn based on Iowa specimens, herpetological research in the state was minor and incidental. Several significant reports appeared after that date involving analysis of Iowa specimens and from 1938 to 1944 a major base-line collection of the amphibians and reptiles of Iowa was established. Studies after that time have added a few species to Iowa’s known herpetofauna but recently have concentrated not only on composition of the fauna and distribution, but emphasized population changes, ecological relationships, and better understanding of life historie

Identification and Distribution of the Treefrogs Hyla versicolor and Hyla chrysoscelis in Iowa

Historically, the tetraploid and diploid species pair of gray treefrogs, Hyla versicolor and Hyla chrysoscelis, were mapped collectively in Iowa because no macroscopic morphological characteristics useful in recognizing the two species had been found. The present study reports identification and separation of the species by counts of nucleoli in the palpebral membrane of the eye and by measurement of scanning electron micrographs of toepad epithelial projections. Subsequent morphometric data confirm that the two species are morphologically distinct in Iowa but that overlap in characters continues to make macroscopic morphology unreliable for identifying individuals. H. chrysoscelis is distributed sporadically though all but the northeastern quarter of Iowa, while H. versicolor is found roughly southeast of a diagonal line extending from the northeastern to the southwestern corner of the state. A genetically different population appears to reside in Cherokee Co. Iowa

Non-Native Amphibians and Reptiles in Iowa

Only a few species appear as introductions into Iowa in the last 30 years. The bullfrog, Rana catesbeiana, was systematically introduced along with fish stocked from hatcheries in the 1930s and this species continues to spread in northern Iowa where it poses a hazard to smaller frogs. Turtles sold as pets, primarily map turtles (Graptemys pseudogeographica and G. geographica) and red-eared turtles (Trachemys scripta) continue to be found in scattered ponds, usually rural, throughout the state. The eastern box turtle (Terrapene carolma) has been reported in or on the edge of most major Iowa cities even though no breeding population is known here. A pregnant Arizona black rattlesnake (Crotalus viridis cerberus) found in a vacant lot in southeastern Des Moines, probably escaped from a snake breeder in the area. The continued existence of a population of salamanders native to the Pacific Northwest that at least temporally established in Davis County after a lumber train derailed there in 1923, is unknown. The spread of the plains spadefoot (Spea bombifrons) throughout the loess hills since 1944 may be an example of a natural introduction. The northern movement of the plains leopard frog (Rana blairi) and the fertilizer-stimulated growth of cattails in shallow marshes that may be impacting survival of Blanding\u27s turtle (Emydoidea blandingi) may be the indirect result of human modification of the environment