Forest stand dynamics were evaluated in a previously managed Quercus-Carya-dominated forest inventoried in 1980 and 2000, a period during which all active forest management was suspended and fire suppression was complete. The diameter distribution superficially resembled a stable unevenaged structure. Over the course of the study, smaller diameter classes were increasingly dominated by shade tolerant species Acer saccharum and Fagus grandifolia across all landscape positions. Diameter distribution changes varied among Quercus species with Q. alba and Q. rubra basal area increasing 63 and 45%, respectively, and Q. velutina decreasing 25% in the >43.2 cm size class. Combined Q. alba, Q. rubra and Q. velutina density decreased 56% in the <27.9 cm size classes.

Transition towards a mesophyte-dominated forest is occurring across all positions in this topographically-diverse landscape, although more slowly on the drier, less productive aspects and slope positions. These changes are comparable to those reported in undisturbed forests of similar overstory composition. The results suggest that sustaining a sizeable component of the presently dominant overstory species will require remedial management strategies that take into account the regeneration requirements of Quercus, Carya and other presently dominant taxa. The decrease in Q. velutina density in the >43.2 cm size class suggests a decline in the regeneration potential of this short lived species.

The effect of floods and base flow on temporal variation in algal biomass on small smooth streambed stones and creviced sand-cases of the caddisfly (Insecta: Trichoptera) Gumaga nigricula was examined in Big Sulphur Creek in coastal Northern California. Replicates of stones and cases were sampled 34 times over a 14 mo period that included nine floods. Stones had ∼2× the algal biomass of cases, based on chlorophyll a concentration. The lower algal biomass on caddisfly cases is consistent with this species' burrowing behavior, which reduces algal biomass by abrasion and light limitation. Algal biomass on stones was reduced by floods and generally increased in the absence of floods. In contrast, neither floods nor extended base flow affected the pattern of algal biomass on caddisfly cases, and biomass on caddisfly cases often exceeded that on stones following floods. Streambed substrates with different textures may provide different degrees of disturbance-protection for benthic microalgae, and rougher substrates in streams may have more relict algae following floods than smoother substrates.

We used low-density seed additions to measure seed predation in eight 8-m × 8-m experimental plots at three prairie sites in 2002 and 20 experimental plots at each site in 2003. We added plant litter to one-half of the experimental plots (treatments), but not the other half (controls). Within each treatment and control plot, we established two seed plots, one available to all consumers and one available only to invertebrates. Seed removal by invertebrates did not differ between treatments and controls for any site or in either year. All consumers, collectively, removed significantly more seed from control plots in tallgrass prairie in both years but more seed from control plots in mixed-grass and shortgrass prairies only in 2003. These patterns suggested that rodents were the primary cause of differences in seed use between control and litter-augmented plots in the three prairie types; and plant litter in central North American grasslands negatively affects seed removal by rodents, but not ants.

The grass shrimp Palaemonetes pugio, a common inhabitant of brackish water marshes, is often used in experimental studies. To support studies concerned with the behavior of P. pugio in controlled laboratory conditions, a behavior catalog (or ethogram) was developed. Twelve grass shrimp activities, six moving and six stationary, were observed and described. The most frequently observed activities included hovering in the water column, walking and three types of swimming. Activities observed less often included backward thrusting, jabbing with the rostrum tip and taking cover. The value of the ethogram was assessed using a predator-prey experiment in which the frequency of grass shrimp behaviors in response the predatory fish Fundulus heteroclitus was examined. In the presence of a fish, grass shrimp decreased the frequency of swimming and increased the frequency of covered and motionless behaviors. We also noted a significant increase in the occurrence of two active antipredator defenses: backward thrust and jabbing with the rostrum tip. Backward thrust quickly propelled shrimp away from a fish. Jabbing with the rostrum tip was directed toward an advancing fish and usually caused the fish to swim off in the opposite direction. These observations provide clues as to the levels and types of interactions that occur between the grass shrimp and their fish predators in the wild. The catalog of recorded activities may be of value in future studies designed to examine the effect of different experimental conditions on grass shrimp behavior.

The crayfish Orconectes neglectus chaenodactylus has recently been introduced into the Spring River drainage in southern Missouri and northern Arkansas and appears to be displacing the native species O. eupunctus. To determine if O. eupunctus and O. neglectus chaenodactylus compete for habitat, we examined if either species shift habitats when in the presence of one another. Habitat use of juvenile and adult crayfish was determined in six habitat types (backwater, pool, riffle, run, stream margin and vegetation) with a quadrat sampler during July/August 2003 at three sites: (1) an upstream site where O. neglectus chaenodactylus occurs, (2) a zone of overlap where both species occur and (3) a downstream site where O. eupunctus occurs. Habitat selection was determined by comparing habitat use to habitat availability. Redundancy Analyses were used to determine the relationship between crayfish densities and measured environmental variables (current velocity, water depth and percent boulder, cobble, pebble and sand). Orconectes eupunctus showed no shift in habitat use, habitat selection and species-environmental relationships between the downstream site and the zone of overlap. However, O. neglectus chaenodactylus did show a shift in habitat use and habitat selection between the upstream site and the zone of overlap, although no shift in species environmental relationships was found. Competition for habitat between O. eupunctus and O. neglectus chaenodactylus did not appear to cause the habitat shift by O. neglectus chaenodactylus since O. neglectus chaenodactylus shifted into habitats used and selected by O. eupunctus. This study suggests that O. eupunctus and O. neglectus chaenodactylus may not compete for habitat. It is possible that habitat is not limiting in this system or that competition is taking place, but at a microhabitat level. Further study is needed to examine other potential mechanisms causing the displacement of O. eupunctus.

Previous (1992–1994) surveys for native freshwater mussels (Unionidae) along main channels of the Detroit River showed that unionids had been extirpated from all but four sites in the upper reaches of the river due to impacts of dreissenid mussels (Dreissena polymorpha and D. bugensis). These four sites were surveyed again in 1998 using the same sampling method (timed-random searches) to determine if they may serve as “refugia” where unionids and dreissenids co-exist. Two additional sites were sampled using additional methods (excavated-quadrat and line-transect searches) for comparison with unpublished data collected in 1987 and 1990. A total of four individuals of four species (Actinonaias ligamentina, Cyclonaias tuberculata, Lasmigona complanata and Pleurobema sintoxia) were found by timed-random searches at four sites in 1998 compared to 720 individuals of 24 species in 1992 and 39 individuals of 13 species in 1994. Excavated-quadrat and line-transect searches at the two additional sites yielded only one live specimen of Ptychobranchus fasciolaris compared to 288 individuals of 18 species in 1987 and 1990. Results of this study suggest that remaining densities of unionids in channels of the Detroit River are too low to support viable reproducing populations of any species. Therefore, we conclude that unionids have been extirpated from main channels of the Detroit River due to dreissenid infestation. As the Detroit River was one of the first water bodies in North America to be invaded by dreissenids, it is likely that unionids will also be extirpated from many other rivers and lakes across eastern North America over the next few decades. Resource agencies should be encouraged to implement active management programs to protect remaining unionid populations from zebra mussels.

Information on life-history traits is critical to understanding population dynamics of anurans. The objective of this study was to examine aspects of the reproductive ecology of Hyla cinerea in northwestern Florida. Four breeding localities in Leon County, Florida, were sampled over three seasons (2001–2003), amplexed pairs were found as early as 12 April and as late as 12 August. Egg clutches were counted from 51 amplexed pairs and adult size was measured in 43 pairs. Average clutch size was 1214 ± 528 eggs (x̄ ± se, range = 359–2658). Female H. cinerea were slightly larger than males (x̄ ± se tibiofibula length = 24.9 ± 2.2 and 24 ± 1.7 mm, respectively). Female size was significantly positively correlated with clutch size and weakly correlated with size of the paired male. Comparison of the results of this study with previous research indicates that the reproductive ecology of H. cinerea varies across its geographic range.

Prescribed fire is used to reduce coverage of woody vegetation in early successional habitats, but burning may also result in direct and indirect mortality of reptiles inhabiting the burn site. Mowing prior to burning has been hypothesized to render grassland habitats unsuitable for the massasauga (Sistrurus catenatus), thereby reducing the number of individuals that may be affected in the management unit at the time of burning. I evaluated the impact of mowing prior to summer burning on massasaugas at Squaw Creek National Wildlife Refuge, in northwestern Missouri, during the summer of 2003 using radiomarked snakes. Pre-burn mowing resulted in the direct mortality of three (43%) of seven radiomarked massasaugas present in the treatment area. Prescribed fire resulted in a mortality of one of two remaining individuals. Pre-burn mowing did not reduce mortalities as hypothesized and likely added to the overall snake mortality rate. Management alternatives other than mowing and prescribed fire when snakes are active should be considered when managing massasauga habitat.

Changes in habitat are often a major influence on species distribution and even survival. Yet predicting habitat often requires detailed field data that are difficult to acquire, especially on private lands. Therefore, we have developed a model that builds on extensive data that are available from public lands and extends them to surrounding private lands. This model is applied for a five-county region in Georgia to predict habitats for the gopher tortoise (Gopherus polyphemus), based on analysis of documented locations of gopher tortoise burrows at the Fort Benning military installation in west central Georgia. Burrow associations with land cover, soil, topography and water observed within the military installation were analyzed with binary logistic regression. This analysis helped generate a probability map for the occurrence of gopher tortoise burrows in the five-county region surrounding Fort Benning. Ground visits were made to test the accuracy of the model in predicting gopher tortoise habitat. The results showed that information on land cover, soils, and distances to streams and roads can be used to predict gopher tortoise burrows. This approach can be used to better understand and effectively carry out gopher tortoise habitat restoration and preservation activities.

Space use and habitat selection have been studied extensively in mammalian carnivores, and it is widely accepted that many factors influence these parameters. Although landscape characteristics are perceived to be important in how carnivores use their environment, relatively few studies have evaluated influences of landscape features on carnivore behavior. We examined relationships between landscape pattern and space use in sympatric bobcats (Lynx rufus), coyotes (Canis latrans) and gray foxes (Urocyon cinereoargenteus) in central Mississippi during 1989–1997. We quantified landscape features within three different spatial scales (3000, 4500 and 6000 m) centered on home ranges of 46 bobcats, 12 coyotes and 22 gray foxes. We evaluated a suite of class- and landscape-level variables and their influence on space use of each species. Linear mixed models suggested that habitat interspersion (intermixing), patch shape (complexity) and edge contrast were important predictors of space use in bobcats. We failed to detect any relationships between landscape pattern and space use of coyotes and gray foxes. We offer that the relationships we observed are related to, and can be explained by, ecology and behavioral adaptations of each species.

Sporadic reports of cougars (Puma concolor) have occurred in Michigan since its official classification as extirpated in the 1930s. We collected 297 scats from 12 areas in Michigan with heavy sighting reports of cougars. Ten scats produced DNA profiles consistent with cougars. One scat was identified as having a North American origin; the other nine scats produced no useable sequences. One pre-Columbian sample, from a Native American burial site; also matched the current North American genotype. Based on the distance between cougar scats, we conclude that there were at least eight cougars in Michigan during the 3 y of this study. The mtDNA sequences also suggest that at least some of the matrilines currently and historically found in Michigan are the same as those found in current and historical western populations.

Some 30 y after wolves (Canis lupus) were implicated in decimating wintering white-tailed deer (Odocoileus virginianus) in a 3000-km² area of northeastern Minnesota, wintering deer still have not recolonized the area. From 1976 to 2004, we aerially radio-tracked wolves there during 250 h and recorded 2 deer (in 1985 and 2000) killed or eaten by wolves during February and March. We observed no other deer or deer sign, but regularly observed deer, deer sign and wolf-killed deer in adjacent wolf-pack territories. Although habitat in the study area generally remains poor, some regeneration has taken place, and deer have increased adjacent to the area. However, wolf numbers have persisted by preying on moose (Alces alces). We could detect no reason other than wolf predation and deer migration traditions for why wintering deer have not recolonized the area.

The purpose of scientific writing is to impart thoughts or ideas and their bases and implications in such a manner that a reading audience, with at least a moderate knowledge of science, can understand the material presented within a paper. This carries the necessity of using words in a manner that clearly impart the intended meaning of the author and not getting off the subject as reflected in the title. Also, the goal of scientific writing is to produce a manuscript written from the perspective of strength, rather than weakness. I discuss appropriate formation of titles such that the intended audience can find the title through bibliographic sources. Also included, to aid in the writing of scientific manuscripts, are discussions of words or sentences with unintended connotations, misuse of words, double entendres, slang, contrived acronyms, jargon, danglers or orphaned clauses and superfluous words. Finally, remember that the object of the art of scientific writing is to communicate in the most concise and precise manner possible, it is not to paint pretty word pictures.

Ranches are being converted to low density exurban housing developments in the southwestern United States, with potentially significant but little studied impacts on biological diversity. We counted lizards in a grassland and mesquite/oak savanna in southeastern Arizona, along 48 transects evenly divided among landscapes that were grazed by livestock, embedded in housing developments, both or neither. Terrestrial lizards as a group (mostly Aspidoscelis uniparens and Holbrookia maculata) were scarce in developed areas, especially where homeowners kept livestock. Combined counts of lizards (Sceloporus clarkii, Sceloporus undulatus and Urosaurus ornatus) associated with three dimensional substrates did not differ among landscape categories. Roadrunners (Geococcyx californianus), known predators of terrestrial lizards, were more common in developed areas, especially those that were grazed. These results are consistent with the hypothesis that the relative scarcity of terrestrial lizards in developed landscapes was due to increased predation by roadrunners, but predation by other species, especially domestic pets, may also have been important.

We describe a previously unreported behavior of black-tailed jackrabbits based on 22 nocturnal observations in northwestern Texas in 1999 and 2000. When being followed at high speeds (40–55 km/h), jackrabbits exhibited four head positions: head up and both ears raised; head up and left ear raised; head up and right ear raised and; head down and no ears raised. While running in a zigzag fashion, jackrabbits changed among the four head positions in rapid succession. Because the ears have conspicuous coloration on the back side (white fur with black-tips), we speculate that ear flashing is an adaptation to confuse predators when being chased at high speeds. Interestingly, this escape behavior is similar to the white rump and side flashing of antelope (Lepus alleni) and white-sided (L. callotis) jackrabbits.

Previous research has found that exposure to fire-related cues enhances germination of some plant species, and such species may exist in frequent-fire southwestern United States Pinus ponderosa forests. I performed four greenhouse experiments with Penstemon barbatus, a perennial forb common in P. ponderosa forests, testing seed responses to liquid and air smoke, charred P. ponderosa wood and leachate, heat and emergence substrates. Liquid smoke increased P. barbatus emergence to as high as 63%, 44% greater than controls, and enhanced emergence in all 4 experiments. Air smoke produced by burning P. ponderosa litter for 15 min appeared to increase emergence similar to liquid smoke. In contrast, P. ponderosa charred wood and charred wood leachate did not improve emergence, and sometimes inhibited positive effects of smoke. Heating samples at 100 C for 30 min did not affect emergence. Substrate and liquid smoke interacted in one experiment, with smoke increasing emergence more sharply on basalt and potting soil than on limestone soil. These greenhouse findings have practical implications for germinating P. barbatus, but need testing under field conditions to evaluate their importance in this species' population biology after fire in P. ponderosa forests.

In the city of Fort Sumner, De Baca Co., New Mexico, the gonochoristic whiptail lizard Aspidoscelis sexlineata viridis is syntopic with two species of allodiploid parthenogenetic lizards, A. tesselata pattern class E and A. neomexicana. A hybrid male lizard was collected on 12 August 2002. Analyses of scutellation and color pattern indicated that this individual is the first known hybrid between A. tesselata E and A. sexlineata viridis.

Anesthesia is often used in amphibian studies, yet little information is available regarding the effectiveness of different anesthetics in the same species and across different life stages. We tested two popular anesthetics, benzocaine and MS-222 (tricaine methanesulfonate), in metamorphic (terrestrial adults) and paedomorphic (aquatic adults) Arizona tiger salamanders (Ambystoma tigrinum nebulosum). Benzocaine induced anesthesia more quickly than MS-222 in the concentration used here (0.02%) and was less variable in induction time. Metamorphic adults had higher and more variable induction times than paedomorphic adults. Recovery time was longer and more variable for animals subject to benzocaine rather than MS-222, but did not vary with morph. Our results suggest that benzocaine has higher per gram effectiveness than MS-222 for this species, which likely underlies the increased suggested dosages in the literature for the latter anesthetic. Such increased effectiveness at low concentrations, along with the monetary and time costs associated with MS-222, suggest that benzocaine is a more efficient and less costly anesthetic than MS-222. Because paedomorphic adults were more susceptible to anesthesia than metamorphic adults, paedomorphs may also be more affected by other aqueous chemicals, including pollutants.

Utilizing data obtained at 3.5-d intervals for a population of Microtus ochrogaster, we compared efficacy of monthly and semi-monthly trapping of small mammal populations in respect to frequency of change of population density, survival and proportion adult females that were reproductively-active. For all three variables, both monthly and semi-monthly intervals closely tracked the 3.5-d intervals. The main exception was the monthly intervals under-recorded by 20% the peak density of one of four population fluctuations during the study; the semi-monthly intervals under-recorded the highest peak density by 4%. Overall, efficacy of a monthly monitoring protocol appeared adequate to describe the three demographic variables and differed little from that of a semi-monthly protocol. Consequently, the additional time and resources required for a semi-monthly trapping protocol do not appear warranted.