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At least 541 records · Page 30Linked to original sources

USGS2003

Actual evapotranspiration and deficit: Biologically meaningful correlates of vegetation distribution across spatial scales

Correlative approaches to understanding the climatic controls of vegetation distribution have exhibited at least two important weaknesses: they have been conceptually divorced across spatial scales, and their climatic parameters have not necessarily represented aspects of climate of broad physiological importance to plants. Using examples from the literature and from the Sierra Nevada of California, I argue that two water balance parameters—actual evapotranspiration (AET) and deficit (D)—are biologically meaningful, are well correlated with the distribution of vegetation types, and exhibit these qualities over several orders of magnitude of spatial scale (continental to local). I reach four additional conclusions. (1) Some pairs of climatic parameters presently in use are functionally similar to AET and D; however, AET and D may be easier to interpret biologically. (2) Several well-known climatic parameters are biologically less meaningful or less important than AET and D, and consequently are poorer correlates of the distribution of vegetation types. Of particular interest, AET is a much better correlate of the distributions of coniferous and deciduous forests than minimum temperature. (3) The effects of evaporative demand and water availability on a site's water balance are intrinsically different. For example, the ‘dry’ experienced by plants on sunward slopes (high evaporative demand) is not comparable to the ‘dry’ experienced by plants on soils with low water-holding capacities (low water availability), and these differences are reflected in vegetation patterns. (4) Many traditional topographic moisture scalars—those that additively combine measures related to evaporative demand and water availability—are not necessarily meaningful for describing site conditions as sensed by plants; the same holds for measured soil moisture. However, using AET and D in place of moisture scalars and measured soil moisture can solve these problems.

Journal of Biogeography↗

USGS2021

Review: “Jacob’s Zoo”— How using Jacob’s method for aquifer testing leads to more intuitive understanding of aquifer characteristics

The interpretation of aquifer responses to pumping tests is an important tool for assessing aquifer geometry and properties, which are critical in the assessment of water resources or in environmental remediation. However, the responses of aquifers, measured by time-drawdown relationships in monitoring wells, are nonunique solutions that are affected by many factors. Jacob’s Zoo is a collection of graphical interpretations that allows students and practitioners to develop an intuitive feel for how natural hydrogeological systems work, and develop a set of skills that provide a better understanding of aquifer properties far beyond interpretation of pumping tests. Jacob’s Zoo, based on the work of Jacob (1950), fosters a deeper understanding, although few practitioners realize the full utility of the method. Jacob CE (1950) Flow of groundwater, In: Rouse H (ed) Engineering Hydraulics, Wiley, New York. P 321–386.

Hydrogeology Journal↗

USGS1980

Mixing models and ionic geothermometers applied to warm (up to 60°C) springs: Jordan Rift Valley, Israel

Mixing models and evaluation of SiO 2 contents of warm-water manifestations in the Jordan—Dead Sea Rift Valley indicate that these waters are fed by aquifers with estimated temperatures of up to 68°C. These calculations and Na/K ratios, concentrations of Na, K and Ca, concentrations of atmospheric Ne, Ar, Kr and Xe; and concentrations of the stable hydrogen and oxygen isotopes all indicate below-boiling temperatures. No indications are available for the existence of above-boiling geothermal systems in the Jordan Rift Valley. Slightly higher than observed temperatures are concluded for a deep component at the springs of Hammat Gader (67°C), Gofra (68°C), the Russian Garden (40°C), and the Yesha well (53–65°C). These temperatures may encourage further developments for spas and bathing installations and, to a limited extent, for space heating, but are not favorable for geothermal power generation.

Journal of Hydrology↗

USGS2023

Wildfire-induced shifts in groundwater discharge to streams identified with paired air and stream water temperature analyses

Within the western United States, increasingly severe and frequent wildfires may alter the magnitude, timing, and quality of water exported from burned areas by streams. Post-fire hydrologic studies often focus on peak stream flow responses to shifts in runoff generation or on annual streamflow yield response to changes in evapotranspiration following fire. However, the magnitude and duration of wildfire effects on groundwater recharge, changes in subsurface routing, and consequences for stream low flows sourced predominately by baseflow are poorly understood. Here, we demonstrate an approach using the amplitude and phase of paired annual air and stream water temperature signals to broadly identify changes in watershed subsurface flow contributions after fire. Watersheds were classified using pre-fire temperature data, as having air-coupled (i.e., reduced apparent groundwater signature), deep groundwater, or shallow groundwater stream temperature signals. Changes in pre- and post-fire paired air and stream water temperature metrics were compared for locations (n = 17) spanning a large range of physiographic and climatic conditions across the western United States. Pre- and post-fire comparisons were computed by quantile using bootstrapped confidence intervals (ci = 95), as well as in aggregate using Kruskal-Wallis and post-hoc Dunn tests. Statistical comparisons of pre- and post-fire temperature metrics suggest that overall, watersheds classified as having minimal groundwater influence are the most likely to experience fire-induced subsurface hydrologic change. More specifically, watersheds classified as having air-coupled or shallow groundwater signals experienced increases in the magnitude of groundwater discharge, with more stable annual thermal regimes post-fire that are less-coupled to ambient air temperature. These findings form the basis of a conceptual framework for watershed resistance to subsurface hydrologic change following fire that can be broadly applied as a first approximation for water management, impacts on aquatic habitat, and post-wildfire response planning.

California, Idaho, Oregon, Washington↗

USGS2017

Indicator-driven conservation planning across terrestrial, freshwater aquatic, and marine ecosystems of the south Atlantic, USA

Systematic conservation planning, a widely used approach to identify priority lands and waters, uses efficient, defensible, and transparent methods aimed at conserving biodiversity and ecological systems. Limited financial resources and competing land uses can be major impediments to conservation; therefore, participation of diverse stakeholders in the planning process is advantageous to help address broad-scale threats and challenges of the 21st century. Although a broad extent is needed to identify core areas and corridors for fish and wildlife populations, a fine-scale resolution is needed to manage for multiple, interconnected ecosystems. Here, we developed a conservation plan using a systematic approach to promote landscape-level conservation within the extent of the South Atlantic Landscape Conservation Cooperative. Our objective was to identify the highest-ranked 30% of lands and waters within the South Atlantic deemed necessary to conserve ecological and cultural integrity for the 10 primary ecosystems of the southeastern United States. These environments varied from terrestrial, freshwater aquatic, and marine. The planning process was driven by indicators of ecosystem integrity at a 4-ha resolution. We used the program Zonation and 28 indicators to optimize the identification of lands and waters to meet the stated objective. A novel part of our study was the prioritization of multiple ecosystems, and we discuss the advantages and disadvantages of this approach. The evaluation of indicator representation within prioritizations was a useful method to show where improvements could be made; some indicators dictated hotspots, some had a limited extent and were well represented, and others had a limited effect. Overall, we demonstrate that a broad-scale (408,276 km 2 of terrestrial and 411,239 km 2 of marine environments) conservation plan can be realized at a fine-scale resolution, which will allow implementation of the regional plan at a local level relevant to decision making.

Journal of Fish and Wildlife Management↗

USGS1991

Acoustic measures of the abundance and size of pelagic planktivores in Lake Michigan

Based on acoustic data taken at night and vertically stratified by bottom depth (3–110 m only), the total number (± 95% Cl) of pelagic fishes in Lake Michigan was 43.4 ± 10.1 x 10 9 or 226.0 ± 55.2 kt in spring (mean density 0.7–3.8 fish·m -2 or 1.6–12.8 ga·m -2 ) and 115.8 ± 18.3 x 109 or 313.2 ± 74.3 kt in late summer, 1987 (mean density 1.1–7.0 fish·m -2 or 3.0–13.2 g·m -2 ); approximately 30% of this increase in numbers (35% of biomass) occurred within Green Bay. Abundance estimates from horizontally stratified (by water column depth) data were within 9-11% of vertically stratified estimates during spring but over 20% higher during summer. By extrapolation to all water depths, we estimated total pelagic biomass as 274.6 kt for spring and 410.8 kt for summer. During both seasons, smaller fishes were nearer to the surface and nearer shore than larger individuals, and acoustic measures of size approximated the sizes of fishes caught in trawls. Bioenergetic model simulations suggest that 60% of the available production of alewife (Alosa pseudoharengus) was either consumed by stocked salmonines (52.9%) or commercially harvested (7.1%) in 1987. Underwater acoustics proved a valuable tool for lakewide assessments of fish abundances in the Great Lakes.

Michigan↗

USGS2008

An hydrothermal experimental study of the cobalt-cobalt oxide redox buffer

Equilibrium aqueous hydrogen concentration and corresponding energies of reaction, ??Grxno(T, P), for the reaction Co(s) + H2O(l) = CoO(s) + H2(aq) have been determined at temperatures between 256 and 355 ??C and at 400 bar. Steady-state concentrations of hydrogen were approached in experiments under conditions of both H2 excess and deficiency containing the solids Co, CoO and liquid water. All experiments were carried out in flexible gold and titanium reactors with the capability of on-line fluid sampling. Measured equilibrium molal concentrations of H2(aq) at 256, 274, 300, 324 and 355 ??C are 0.81(?? 0.01) ?? 10- 3 1.11(?? 0.01) ?? 10- 3, 1.92(?? 0.01) ?? 10- 3, 3.71(?? 0.06) ?? 10- 3, 7.54(?? 0.12) ?? 10- 3, respectively, and corresponding values of ??Grxno(T, P) in units kJ ?? mol- 1 are 31.4(?? 0.1), 31.0(?? 0.1), 29.8(?? 0.1), 27.7(?? 0.5) and 25.5(?? 0.9), respectively. Using published heat capacity data for Co(s) and CoO(s) and - 79.6 J ?? mol- 1 ?? K- 1 for the entropy of formation of CoO we calculated for this study a value for ??GCoO,Tr,Pro = - 214.5(?? 0.9) kJ ?? mol- 1 and ??HCoO,Tr,Pro = - 238.3(?? 0.9) kJ ?? mol- 1 at 25 ??C and 1 bar. The value of ??HCoO,Tr,Pro determined in this study compares well with the reported calorimetric value of - 238.9(?? 1.2) kJ ?? mol- 1 [Boyle, B.J., King, E.G., Conway, K.C., 1954. Heats of formation of nickel and cobalt oxides (NiO and CoO) by combustion calorimetry. Journal of the American Chemical Society, 76, 3835-3837]. ?? 2008 Elsevier B.V. All rights reserved.

Chemical Geology↗

USGS2006

Analysis of the surface hydrology in a regional climate model

This paper discusses the surface hydrology of a multi‐year simulation of present day climate over the United States (US) conducted with a regional climate model (RegCM) nested within a general circulation model (GCM). The RegCM, which is run with a 60 km gridpoint spacing is interactively coupled with a state‐of‐the‐art surface physics package that includes full surface hydrology calculations (the Biosphere‐Atmosphere Transfer Scheme or BATS). The hydrologic budgets of ten regional drainage basins in the US are analysed. Model results are compared with available observations and with results from previous modelling experiments to evaluate the feasibility of using nested RegCM/GCM models for hydrology studies. In our experiment, the model captures the basic seasonality of the basin hydrologic budgets, although the simulated precipitation amounts are too high over the western US and too low over the eastern US. As a result, runoff, snow cover and soil water content are underestimated over the eastern US basins, while evaporation and runoff are overestimated in some of the western US basins. Topographically induced characteristics of precipitation, snow cover and runoff are well simulated over the mountainous western regions. Also well captured is the inter‐basin variation of hydrologic budgets which occurs in response to different climatic settings. The springtime snowmelt and peak runoff season generally occurs in the model earlier in the year than is observed. Although our work indicates that the coupled regional modelling system can be useful in applications to hydrological studies, results from this experiment indicate that better accuracy in the simulation of regional climatic variables and more detailed representation of some hydrologic processes would be required before the coupled modelling system could be used to provide accurate assessments of hydrologic responses to climate change.

Quarterly Journal of the Royal Meteorological Soci↗

USGS2003

Nitrate distributions and source identification in the Abbotsford-Sumas Aquifer, northwestern Washington State

The Abbotsford–Sumas Aquifer is a shallow, predominantly unconfined aquifer that spans regions in southwestern British Columbia, Canada and northwestern Washington, USA. The aquifer is prone to nitrate contamination because of extensive regional agricultural practices. A 22-month ground water nitrate assessment was performed in a 10-km 2 study area adjacent to the international boundary in northwestern Washington to examine nitrate concentrations and nitrogen isotope ratios to characterize local source contributions from up-gradient sources in Canada. Nitrate concentrations in excess of 10 mg nitrate as nitrogen per liter (mg N L −1 ) were observed in ground water from most of the 26 domestic wells sampled in the study area, and in a creek that dissects the study area. The nitrate distribution was characteristic of nonpoint agricultural sources and consistent with the historical documentation of agriculturally related nitrate contamination in many parts of the aquifer. Hydrogeologic information, nitrogen isotope values, and statistical analyses indicated a nitrate concentration stratification in the study area. The highest concentrations (>20 mg N L −1 ) occurred in shallow regions of the aquifer and were linked to local agricultural practices in northwestern Washington. Nitrate concentrations in excess of 10 mg N L −1 deeper in the aquifer (>10 m) were related to agricultural sources in Canada. The identification of two possible sources of ground water nitrate in northwestern Washington adds to the difficulty in assessing and implementing local nutrient management plans for protecting drinking water in the region.

Washington, British Columbia↗

USGS2008

Near-decadal changes in nitrate and pesticide concentrations in the South Platte River alluvial aquifer, 1993-2004

The lower South Platte River basin of Colorado and Nebraska is an area of intense agriculture supported by surface-water diversions from the river and ground-water pumping from a valley-fill alluvial aquifer. Two well networks consisting of 45 wells installed in the South Platte alluvial aquifer were sampled in the early 1990s and again in the early 2000s to examine near-decadal ground-water quality changes in irrigated agricultural areas. Ground-water age generally increases and dissolved-oxygen content decreases with distance along flow paths and with depdi below the water table, and denitrification is an important natural mitigation mechanism for nitrate in downgradient areas. Ground-water travel time from upland areas to the river ranges from 12 to 31 yr on the basis of apparent ground-water ages. Ground-water nitrate concentrations for agricultural land-use wells increased significantly for oxidized samples over the decade, and nitrogen isotope ratios for oxidized samples indicate synthetic fertilizer as the predominant nitrate source. Ground-water concentrations of atrazine, DEA, and prometon decreased significandy. The decrease in pesticide concentrations and a significant increase in the ratio of DEA to atrazine suggest decreases in pesticide concentrations are likely caused by local decreases in application rates and/or degradation processes and that atrazine degradation is promoted by oxidizing conditions. The difference between results for oxidizing and nitrate-reducing conditions indicates redox state is an important variable to consider when evaluating ground-water quality trends for redox-sensitive constituents such as nitrate and pesticides in the South Platte alluvial aquifer. Copyright ?? 2008 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved.

Journal of Environmental Quality↗

USGS2016

Observations of nearshore groundwater discharge: Kahekili Beach Park submarine springs, Maui, Hawaii

Study region The study region encompasses the nearshore, coastal waters off west Maui, Hawaii. Here abundant groundwater—that carries with it a strong land-based fingerprint—discharges into the coastal waters and over a coral reef. Study focus Coastal groundwater discharge is a ubiquitous hydrologic feature that has been shown to impact nearshore ecosystems and material budgets. A unique combined geochemical tracer and oceanographic time-series study addressed rates and oceanic forcings of submarine groundwater discharge at a submarine spring site off west Maui, Hawaii. New hydrological insights for the region Estimates of submarine groundwater discharge were derived for a primary vent site and surrounding coastal waters off west Maui, Hawaii using an excess 222 Rn ( t 1/2 = 3.8 d) mass balance model. Such estimates were complemented with a novel thoron ( 220 Rn, t 1/2 = 56 s) groundwater discharge tracer application, as well as oceanographic time series and thermal infrared imagery analyses. In combination, this suite of techniques provides new insight into the connectivity of the coastal aquifer with the near-shore ocean and examines the physical drivers of submarine groundwater discharge. Lastly, submarine groundwater discharge derived constituent concentrations were tabulated and compared to surrounding seawater concentrations. Such work has implications for the management of coastal aquifers and downstream nearshore ecosystems that respond to sustained constituent loadings via this submarine route.

Hawaii↗

USGS1997

Predicting travel time and dispersion in rivers and streams

The possibility of a contaminant being accidentally or intentionally spilled in a river is a constant concern to those using the water. Methods are developed to estimate: (1) the velocity of a contaminant in a river; (2) the rate of attenuation of the peak concentration of a conservative contaminant; and (3) the time required for a contaminant plume to pass a point. The methods are based on data collected by the U.S. Geological Survey in almost a hundred different rivers representing a wide range of sizes, slopes, and geomorphic types. Although the accuracy of the predictions can be greatly increased by performing time-of-travel studies, the emphasis of this paper is on providing methods for making estimates where few data are available. It is shown that the unit-peak concentration is well correlated with travel time and that the travel time of the leading edge averages 89% of the travel time of the peak concentration.

Journal of Hydraulic Engineering↗

USGS2007

Altered stream-flow regimes and invasive plant species: The Tamarix case

Aim: To test the hypothesis that anthropogenic alteration of stream-flow regimes is a key driver of compositional shifts from native to introduced riparian plant species. Location: The arid south-western United States; 24 river reaches in the Gila and Lower Colorado drainage basins of Arizona. Methods: We compared the abundance of three dominant woody riparian taxa (native Populus fremontii and Salix gooddingii, and introduced Tamarix) between river reaches that varied in stream-flow permanence (perennial vs. intermittent), presence or absence of an upstream flow-regulating dam, and presence or absence of municipal effluent as a stream water source. Results: Populus and Salix were the dominant pioneer trees along the reaches with perennial flow and a natural flood regime. In contrast, Tamarix had high abundance (patch area and basal area) along reaches with intermittent stream flows (caused by natural and cultural factors), as well as those with dam-regulated flows. Main conclusions: Stream-flow regimes are strong determinants of riparian vegetation structure, and hydrological alterations can drive dominance shifts to introduced species that have an adaptive suite of traits. Deep alluvial groundwater on intermittent rivers favours the deep-rooted, stress-adapted Tamarix over the shallower-rooted and more competitive Populus and Salix. On flow-regulated rivers, shifts in flood timing favour the reproductively opportunistic Tamarix over Populus and Salix, both of which have narrow germination windows. The prevailing hydrological conditions thus favour a new dominant pioneer species in the riparian corridors of the American Southwest. These results reaffirm the importance of reinstating stream-flow regimes (inclusive of groundwater flows) for re-establishing the native pioneer trees as the dominant forest type. ?? 2007 The Authors Journal compilation ?? 2007 Blackwell Publishing Ltd.

Global Ecology and Biogeography↗

USGS2013

Historical groundwater trends in northern New England and relations with streamflow and climatic variables

Water-level trends spanning 20, 30, 40, and 50 years were tested using month-end groundwater levels in 26, 12, 10, and 3 wells in northern New England (Maine, New Hampshire, and Vermont), respectively. Groundwater levels for 77 wells were used in interannual correlations with meteorological and hydrologic variables related to groundwater. Trends in the contemporary groundwater record (20 and 30 years) indicate increases (rises) or no substantial change in groundwater levels in all months for most wells throughout northern New England. The highest percentage of increasing 20-year trends was in February through March, May through August, and October through November. Forty-year trend results were mixed, whereas 50-year trends indicated increasing groundwater levels. Whereas most monthly groundwater levels correlate strongly with the previous month's level, monthly levels also correlate strongly with monthly streamflows in the same month; correlations of levels with monthly precipitation are less frequent and weaker than those with streamflow. Groundwater levels in May through August correlate strongly with annual (water year) streamflow. Correlations of groundwater levels with streamflow data and the relative richness of 50- to 100-year historical streamflow data suggest useful proxies for quantifying historical groundwater levels in light of the relatively short and fragmented groundwater data records presently available.

Maine;New Hampshire;Vermont↗

USGS2002

Evaluation of canoe surveys for anurans along the Rio Grande in Big Bend National Park, Texas

Surveys for amphibians along large rivers pose monitoring and sampling problems. We used canoes at night to spotlight and listen for anurans along four stretches of the Rio Grande in Big Bend National Park, Texas, in 1998 and 1999. We explored temporal and spatial variation in amphibian counts and species richness and assessed relationships between amphibian counts and environmental variables, as well as amphibian-habitat associations along the banks of the Rio Grande. We documented seven anuran species, but Rio Grande leopard frogs ( Rana berlandieri ) accounted for 96% of the visual counts. Chorus surveys along the river detected similar or fewer numbers of species, but orders of magnitude fewer individuals compared to visual surveys. The number of species varied on average by 37% across monthly and nightly surveys. We found similar average coefficients of variation in counts of Rio Grande leopard frogs on monthly and nightly bases (CVs = 42–44%), suggesting that canoe surveys are a fairly precise technique for counts of this species. Numbers of Rio Grande leopard frogs observed were influenced by river gage levels and air and water temperatures, suggesting that surveys should be conducted under certain environmental conditions to maximize counts and maintain consistency. We found significant differences in species richness and bullfrog ( Rana catesbeiana ) counts among the four river stretches. Four rare anuran species were found along certain stretches but not others, which could represent either sampling error or unmeasured environmental or habitat differences among the river stretches. We found a greater association of Rio Grande leopard frogs with mud banks compared to rock or cliff (canyon) areas and with seepwillow and open areas compared to giant reed and other vegetation types. Canoe surveys appear to be a useful survey technique for anurans along the Rio Grande and may work for other large river systems as well.

Texas↗

USGS1998

Groundwater geochemistry of Isla de Mona, Puerto Rico

In this study, we explore the differences between the hydrogeochemical processes observed in a setting that is open to input from the land surface and in a setting that is closed with respect to input from the land surface. The closed setting was a water-filled passage in a cave. Samples of groundwater and of a solid that appeared to be suspended in the relatively fresh region of saline-freshwater mixing zone were collected. The solid was determined to be aragonite. Based on the analyses of the composition and saturation state of the groundwater, the mixing of fresh and saline water and precipitation of aragonite are the controlling geochemical processes in this mixing zone. We found no evidence of sulfate reduction. Thus, this mixing zone is similar to that observed in Caleta Xel Ha, Quintana Roo, also a system that is closed with respect to input from the land surface. The open setting was an unconfined aquifer underlying the coastal plain along which four hand-dug wells are located. Two wells are at the downgradient ends of inferred flowpaths and one is along a flowpath. The composition of the groundwater in the downgradient wells is sulfide-rich and brackish. In contrast, at the well located along a flow line, the groundwater is oxygenated and brackish. All groundwater is oversaturated with respect to calcite, aragonite, and dolomite. The composition is attributed to mixing of fresh and saline groundwater, CO2 outgassing, and sulfate reduction. This mixing zone is geochemically similar to that observed in blue holes and cenotes.

Journal of Cave and Karst Studies↗

USGS1972

Lake Michigan: effects of exploitation, introductions, and eutrophication on the salmonid community

Lake Michigan surface area is 22,400 square miles and its main depth is 276 ft. Its fauna is generally typical of North American oligotrophic lakes. The original fish populations included 10 coregonines and one salmonine. The lake whitefish, the lake herring, and the lake trout were most abundant. Man's activities have caused great changes in the lake in the past 120 years. Although changes in water chemistry and in the lower biota have been generally modest (except locally), those in salmonid communities have been vast. Exploitation, exotic fish species (especially the sea lamprey and alewife), and accelerated eutrophication and other pollution, all have played a role in bringing about the modifications (mostly marked declines in abundance) in salmonid communities. Commercial exploitation was largely responsible for the changes in the salmonid communities before the invasion of the lamprey (1936), although eutrophication and other pollution, and alterations of spawning streams, also were important. The lamprey and alewife (first reported in 1949), however, have exerted a greater impact than the other factors in recent decades.

Journal of the Fisheries Research Board of Canada↗

USGS2012

Body condition of Morelet’s Crocodiles ( Crocodylus moreletii ) from northern Belize

Body condition factors have been used as an indicator of health and well-being of crocodilians. We evaluated body condition of Morelet's Crocodiles ( Crocodylus moreletii ) in northern Belize in relation to biotic (size, sex, and habitat) and abiotic (location, water level, and air temperature) factors. We also tested the hypothesis that high water levels and warm temperatures combine or interact to result in a decrease in body condition. Size class, temperature, and water level explained 20% of the variability in condition of Morelet's Crocodiles in this study. We found that adult crocodiles had higher condition scores than juveniles/subadults but that sex, habitat, and site had no effect. We confirmed our hypothesis that warm temperatures and high water levels interact to decrease body condition. We related body condition of Morelet's Crocodiles to natural fluctuations in air temperatures and water levels in northern Belize, providing baseline conditions for population and ecosystem monitoring.

Journal of Herpetology↗