Forest In Illinois Research Articles

Influence of natal habitat preference on habitat selection during extra-home range movements in a large ungulate.

Natal habitat preference induction (NHPI) occurs when animals exhibit a preference for new habitat that is similar to that which they experienced in their natal environment, potentially leading to post-dispersal success. While the study of NHPI is typically focused on post-settlement home ranges, we investigated how this behavior may manifest during extra-home range movements (EHRMs), both to identify exploratory prospecting behavior and assess how natal habitat cues may influence path selection before settlement. We analyzed GPS collar relocation data collected during 79 EHRMs made by 34 juvenile and subadult white-tailed deer (Odocoileus virginianus) across an agricultural landscape with highly fragmented forests in Illinois, USA. We developed a workflow to measure multidimensional natal habitat dissimilarity for each EHRM relocation and fit step-selection functions to evaluate whether natal habitat similarity explained habitat selection along movement paths. Across seasons, selection for natal habitat similarity was generally weak during excursive movements, but strong during dispersals, indicating that NHPI is manifested in dispersal habitat selection in this study system and bolstering the hypothesis that excursive movements differ functionally from dispersal. Our approach for extending the NHPI hypothesis to behavior during EHRMs can be applied to a variety of taxa and can expand our understanding of how individual behavioral variation and early life experience may shape connectivity and resistance across landscapes.

Accelerated gross nitrogen cycling following garlic mustard invasion is linked with abiotic and biotic changes to soils

IntroductionAlliaria petiolata (garlic mustard), an invasive forest herb in North America, often alters nutrient availability in its non-native ecosystems, but the mechanisms driving these changes have yet to be determined. We hypothesized three potential mechanisms through which garlic mustard could directly influence soil nitrogen (N) cycling: by increasing soil pH, by modifying soil microbial community composition, and by altering nutrient availability through litter inputs.Materials and methodsTo test these hypotheses, we evaluated garlic mustard effects on soil pH and other soil properties; fungal and prokaryotic (bacterial and archaeal) community composition; and soil N cycling rates (gross N mineralization and nitrification rates, microbial N assimilation rates, and nitrification- versus denitrification-derived nitrous oxide fluxes); and we assessed correlations among these variables. We collected soil samples from garlic mustard present, absent, and removed treatments in eight forests in central Illinois, United States, during the rosette, flowering, and senescence phenological stages of garlic mustard life cycle.ResultsWe found that garlic mustard increased soil pH, altered fungal and prokaryotic communities, and increased rates of N mineralization, nitrification, nitrification-derived net N2O emission. Significant correlations between soil pH and microbial community composition suggest that garlic mustard effects on soil pH could both directly and indirectly influence soil N cycling rates.DiscussionCorrespondence of gross rates of N mineralization and nitrification with microbial community composition suggest that garlic mustard modification of soil microbial communities could directly lead to changes in soil N cycling. We had expected that early season, nutrient-rich litter inputs from mortality of young garlic mustard could accelerate gross N mineralization and microbial N assimilation whereas late season, nutrient poorer litter inputs from senesced garlic mustard could suppress N mineralization, but we did not observe these patterns in support of the litter input mechanism. Together, our results elucidate how garlic mustard effects on soil pH and microbial community composition can accelerate soil N cycling to potentially contribute to the invasion success of garlic mustard.

Soil microbial communities are not altered by garlic mustard in recently invaded central Illinois forests

AbstractThe invasive forest plant garlic mustard (Alliaria petiolata) has been shown to alter soil microbial communities in the northeastern part of its invaded range in the United States, and this disruption of soil communities may contribute to its invasion success. However, garlic mustard allelochemistry can vary with invasion age, and it is not clear whether garlic mustard's impacts on soil microbes are consistent over its invaded range. Here, we compare the composition and diversity of soil fungal, bacterial, and archaeal communities among garlic mustard present, absent, and removed treatments in replicated blocks across five forests in the midwestern United States with relatively young garlic mustard invasions (approximately 17–26 years old, with consistent management). We collected samples in May and August, corresponding to garlic mustard active and senescent life history stages. While soil fungal and bacterial/archaeal communities (based on ITS2 region and 16S rRNA gene DNA sequencing, respectively) differed significantly between different blocks/forests and over time, we found no significant effect of garlic mustard treatment on soil microbial community composition or the relative abundance of mycorrhizal, saprotrophic, or pathogenic fungal guilds. The lack of garlic mustard impacts on the soil microbial community in recently invaded central Illinois forests suggests that these well‐documented impacts in the northeastern United States and in older invasions cannot necessarily be generalized across all environmental contexts.

Interspecific wood trait variation predicts decreased carbon residence time in changing forests

Abstract Increasing disturbance will result in a significant flux in above‐ground carbon (C) from live trees to deadwood, concurrent with shifts in forest composition. While interspecific decay variation is widely reported, the implications of compositional change on ecosystem‐level deadwood decay and consequently the future of a globally significant C pool have not been previously explored. Leveraging a 25‐year treefall record for two eastern hardwood forests in central Illinois, USA, we used a chronosequence approach to estimate downed deadwood decay rates for eight common tree taxa. We hypothesized that the increasing dominance of Acer spp. in eastern forests, due to disturbance regime changes, is driving an increase in the mean species‐weighted deadwood decay rate, decreasing the total C storage capacity of regional forests. We observed significantly greater interspecific variation in deadwood decay rates than short‐term studies, with a nearly 12‐fold difference in half‐lives between Aesculus glabra (T1/2 = 6.2 years) and Quercus spp. (T1/2 = 71.1) logs. The canopy‐dominant Acer saccharum (T1/2 = 19.1) decayed significantly faster than other historically dominant eastern taxa, Quercus spp. and Fraxinus spp. (T1/2 = 41.4). Wood traits, notably taxon initial wood C:N ratio, pH and Mn concentration, outweighed local environmental factors in explaining variation in decay rates. Taken together, our findings suggest that at multi‐decadal time‐scales, species traits are the dominant controls of wood decay rates. Our findings corroborate previous studies showing species with slow‐decaying wood tend to have higher C:N ratios. Our species‐specific decay estimates highlight the importance of longer term studies for accurately assessing the decay of high C:N ratio species, as shorter term decay studies are prone to underestimating their decay rates. Our results suggest that ongoing forest compositional changes, where fast‐growing species with less‐dense wood are becoming increasingly abundant, have substantially diminished the deadwood C pool over the last century (species abundance‐weighted mean T1/2 in 1922 = 16.9; T1/2 2020 = 10.5). A free Plain Language Summary can be found within the Supporting Information of this article.

Niche ecology in Floristic Quality Assessment: Are species with higher conservatism more specialized?

Floristic Quality Assessment (FQA) metrics are used to assess the conservation value of natural areas based on the composition of their plant communities. FQA is based on coefficients of conservatism (C-values). C-values are regional, expert-assigned values, which range from 0 to 10 to reflect a taxon’s fidelity to high quality natural areas and its relative tolerance to modern human impacts. Approximately half of FQA publications assert without evidence that plant species with lower C-values are more generalist, whereas species with higher C-values are habitat specialists. The connection between specialization and C-values has never been investigated. Our primary objective was to test the claim that ecological specialization is associated with C-values. We first used the “theta (θ) method,” based on species co-occurrences, to estimate niche width for 274 species in 598 wetlands, grasslands, and forests in Illinois, USA. As a secondary proxy for niche width, we counted the habitat preferences of all Illinois vascular taxa listed from the Illinois Plant Information Network (ILPIN). For θ in grasslands and wetlands, and for ILPIN habitat counts, the lowest and highest C-values were associated with greater ecological specialization, whereas species with low to intermediate C-values were the most generalist. In forests, we found weaker, negatively linear relationships between C-values and θ, indicating that species with a high conservation value (i.e. conservative) were the most specialized. However, when shrub and canopy layers were combined with the herbaceous layer data in forests, we did not find an association between C-values and specialization. We also reanalyzed the data to determine the effect of non-native species on the relationship between niche width and C-values because non-native species, by default, receive C-values of 0. Removing non-native species from the analyses did not influence our conclusions. Both methods to measure specialization suggested there is a weak relationship between C-values and ecological specialization. Our findings support the common claim that some conservative species are more specialized than species with intermediate or low C-values. However, we found the general C-value and specialization relationship is more complex than assumed by many FQA publications because if it exists, it is not necessarily linear, i.e., species with low C-values are often specialists. Specialization and niche width could be latent components of C-values, but FQA users should avoid defining species conservatism by niche and specialization.

Dynamics of Soil Organic Carbon Storage and Erosion due to Land Use Change (Illinois, USA)

Many factors including land use, management history, soil series, climate, and soil landscape processes affect the dynamics of soil organic carbon (SOC). The primary objective of this research was to determine the impact of land use change from timberland to cropland on erosion and the SOC storage on sloping landscapes of northwestern Illinois, USA. Typic Hapludalfs and Aquic Udifluvents were studied. The cropland area was previously cultivated from 1860 to 1929, between 1930 and 1979 the area was used for pastureland and was returned to cropland from 1980 to 2009. Since 1980, corn and soybean were grown on a yearly rotation system using a no-tillage system. The timberland area was never cleared and cultivated but was subjected to periodic grazing from 1860 to 2009. The SOC concentration of various soil layers, to a depth of 0.5 m, was measured and expressed on a volumetric basis. For both land uses, the subsurface layers had similar SOC levels. Results suggested that after 150 years the cropland landscape maintained or retained 69.4% of the total SOC of timberland on a volumetric basis. The other 30.6% of the SOC was either deposited in the water or released to atmosphere. This study only included SOC and did not attempt to address or include the amount of C stored in above ground timberland trees or cropland plants or in their root systems. Results suggest that if northwestern Illinois forest soils are cleared and used for cropland during the next 50 years, SOC will be retained in the sediment on lower landscape segments, released to atmosphere as CO2 or released to stream (water) in solution or attached to sediment. The initial timberland SOC levels will not be maintained when converted to cropland use even with a crop rotation which includes small grains and forages and no-till management systems for corn and soybean production. This land use conversion from timberland to cropland would result in greater SOC loss than if the area remained as forestland.

Decline in herb species diversity over two decades in a temperate deciduous forest in Illinois

Abstract Over the past century, the abundance of many plant species has declined noticeably, including in the herbaceous understory of temperate deciduous forests. Two separate censuses of Trelease Woods in Illinois, USA, one in 1994–95 that was repeated in 2015, and a second made annually from 1994–2015, indicated major losses for herb species. Quadrat frequency, flowering quadrat frequency, number of species, number of species in flower, number of individuals, and species diversity (H′) all declined greatly over the census period. Most species saw a marked decline in frequency and density, with the number of individuals declining by two-thirds and some species disappearing entirely. Gains from new colonization were minor in comparison. Among persisting species, almost all became shorter and stopped flowering. Number of individuals per species in 1994 and percentage of individuals lost by 2015 were not related. Spring ephemeral species had less loss in frequency and percentage of individuals lost per spe...

Influence of Trap Height and Bait Type on Abundance and Species Diversity of Cerambycid Beetles Captured in Forests of East-Central Illinois.

We assessed how height of panel traps above the forest floor, and the type of trap bait used, influenced the abundance and diversity of cerambycid beetles caught in forested areas of east-central Illinois. Panel traps were suspended from branches of hardwood trees at three heights above the ground: understory (∼1.5 m), lower canopy (∼6 m), and midcanopy (∼12 m). Traps were baited with either a multispecies blend of synthesized cerambycid pheromones or a fermenting bait mixture. Traps captured a total of 848 beetles of 50 species in the cerambycid subfamilies Cerambycinae, Lamiinae, Lepturinae, and Parandrinae, and one species in the closely related family Disteniidae. The species caught in highest numbers was the cerambycine Anelaphus pumilus (Newman), represented by 349 specimens. The 17 most abundant species (mean ± 1 SD: 45 ± 80 specimens per species) included 12 cerambycine and five lamiine species. Of these most abundant species, 13 (77%) were attracted to traps baited with the pheromone blend. Only the cerambycine Eburia quadrigeminata (Say) was attracted by the fermenting bait. Three species were captured primarily in understory traps, and another five species primarily in midcanopy traps. Variation among cerambycid species in their vertical distribution in forests accounted for similar overall abundances and species richness across trap height treatments. These findings suggest that trapping surveys of native communities of cerambycids, and quarantine surveillance for newly introduced exotic species, would be optimized by including a variety of trap baits and distributing traps across vertical strata of forests.

Intellectual preparedness: Dr. Hu Shih, Lake Forest College, and Chinese diplomacy during World War II

The summer of 1941 was a critical juncture in WWII history. As the war intensified and threatened the security of the United States, the American people were sharply divided into two opposing political camps, one sympathetic to interventionism and the other in favor of isolationism. Frightened by the recent memory of WWI and the reality of a worldwide economic depression, many Americans believed that their country should separate itself from troubling events in the world, thereby refuting President Roosevelt’s call for America to intervene against Hitler’s aggression in Europe and Japan’s atrocities in Asia. Against this historical background, Dr. Hu Shih, Chinese ambassador to the United States, came to Lake Forest in Illinois, the center of the isolationist movement, in the summer of 1941 to deliver a speech at Lake Forest College’s Sixty-Third Annual Commencement. This article uses various archives to reveal an untold story about Dr. Hu’s speech-diplomacy during his ambassadorial career. Tied to this event was a drama conveyed via multiple layers of historical accounts and contextualized by a series of political discourses ranging from the rise of isolationism in America to China’s use of soft-power diplomacy in the international arena, in which Dr. Hu played a significant role.

Intensive Selective Deer Browsing Favors Success ofAsimina triloba(Paw Paw) a Native Tree Species

ABSTRACT: Although white-tailed deer (Odocoileus virginianus Zimmermann) are generalist herbivores, they can have significant effects on species composition and abundance of forest trees, especially when deer densities are high and most plant species are heavily browsed but a few are selectively avoided as browse. We evaluated effects of selective deer browsing on tree species abundance in an old-growth mesic/wet-mesic forest in central Illinois by repeated sampling of permanent study plots in 2003 and 2008 and relating changes in stem density between the two samples to the intensity of deer browsing of individual species. The study site has high deer density (75 deer km2) during winter months, and initial observations indicated that paw paw (Asimina triloba (L.) Dunal) was strongly avoided as browse. Paw paw density increased in the seedling stratum between the two sample periods. However, nearly all other tree species declined in density; blue ash (Fraxinus quadrangulata Michx.) — a low-use browse speci...

Effects of forest composition on trophic relationships among mast production and mammals in central hardwood forest

Abstract Oak-dominated forest has declined in the eastern United States as shade-tolerant mesophytic species (e.g., maple [Acer spp.]) replace oaks (Quercus spp.), sparking concern among ecologists regarding species that consume acorns. Our goal was to describe how increasing mesophication of oak forests may affect consumers in higher trophic levels. We investigated relationships among forest composition, mast production, small-mammal density, and carnivore occurrence in 8 stands representing a gradient of oak–hickory dominance in central hardwood forest in southern Illinois. We livetrapped small mammals for >24,000 trap-nights in June–August 2009–2011 with trapping webs to estimate population density of mice (Peromyscus spp.). We collected mast seeds during October–November 2009–2010 and calculated average dry biomass (g/m2) for each species and stand. During winters 2009–2011, we photographed carnivores using baited camera traps. We regressed mast biomass on measures of forest composition and regressed ...

Differential response of nest predators to the presence of a decoy parent in artificial nests

Capsule Mammalian and avian predators respond differently to decoys. Aims To investigate if parental attendance, which is often not accounted for in artificial nest studies, could alter predator guilds and predation rates. Methods To analyze the effects of simulated parental attendance on nest predation trends we implemented decoys of mounted American Robin Turdus migratorius specimens. We set up 22 nest-sites in an Illinois (USA) forest with control (no decoy) and experimental (with decoy) nests, the latter of which simulated parental attendance. Motion-sensitive cameras and bite-mark impressions on plasticine eggs and quail eggs identified predators. Results We found that simulated parental attendance significantly reduced nest predation rates: 61% of the 22 paired treatments were totally depredated, and more control nests (77.3%) were depredated in comparison with nests with decoys (9.1%). Mammalian predators predominantly attacked nests with decoys and avian predators predominantly attacked control nests. Conclusions Using taxidermic decoys in artificial nest experiments may improve the emulation of predation trends of natural nests, while revealing that parental attendance differentially affects predators.

Species and temporal factors affect predator-specific rates of nest predation for forest songbirds in the Midwest

ABSTRACT. Knowledge of the relative contributions of predator species to overall rates of nest predation can improve our understanding of why predation risk varies, but the identity of predators is seldom known. We used video technology to identify nest predators of the tree-nesting Acadian Flycatcher (Empidonax virescens) and the shrub-nesting Indigo Bunting (Passerina cyanea) in forests of Missouri and southern Illinois. Raptors, snakes, and nonraptorial birds were the most frequent nest predators; rodents depredated fewer nests; and mesopredators rarely depredated nests. We tested hypotheses concerning effects of songbird species, ordinal date, nest stage, height, and age on overall and predator-specific predation rates to determine whether variation in overall predation rates was attributable to a subset of nest predators. Overall predation rates were higher for Indigo Buntings than for Acadian flycatchers, were higher during the nestling stage than during incubation, and exhibited a midseason peak. C...

The Illinois Forest Preserve District Act of 1913 and the emergence of metropolitan park system planning in the USA

In 1913, the Illinois Legislature enacted the Forest Preserve District Act. After adoption of the Act by voters in Cook County, the Chicago metropolitan area became among the first in the USA to establish a park system with an outer ring of nature preserves. This article chronicles the story of how the Cook County Forest Preserve District was established, its historical context and its influence on planning practice. It contends that although Chicago was not the originator of the idea of outer parks, it added significantly to development of the concept of comprehensive park system planning. The article contends that the paradigm of park management changed from conservation of the native landscape to multiple use management during the 20‐year struggle to establish the district, and that passage of the Act was largely the result of the efforts of two individuals – Dwight Perkins and Jens Jensen.

Temporal changes in species composition in permanent plots across the Shawnee National Forest, Illinois, USA1

Abstract Species composition in three strata of 63 permanent plots across two physiographic divisions (Ozark Hills and Shawnee Hills) of the Shawnee National Forest (SNF) in southern Illinois was resampled 3–6 years after initial establishment with the objective to assess short-term changes in species composition. Environmental data collected at each plot included overhead canopy cover, elevation, solar radiation, slope, and a suite of nine soil properties. Basal area of the trees in the Ozark Hills Division did not change, but total basal area and basal area of Carya ovata, Fraxinus americana, Quercus rubra, and Ulmus alata increased in the Shawnee Hills Division. In the woody understory, there was an increase in the density of Acer saccharum, C. florida, F. americana, and U. alata in the Shawnee Hills Division, and a decrease in density of C. florida and Fagus grandifolia in the Ozark Hills Division. The decrease in C. florida in the Ozark Hills Division is likely due to an infestation of Discula destru...

Long-term spatial dynamics of Acer saccharum during a population explosion in an old-growth remnant forest in Illinois

Species richness and evenness have greatly declined in oak–hickory forests in the central hardwood region in the U.S.A. in the past 100 years due to the rapid population growth of Acer saccharum. This study used a 50-year record of spatial dynamics to examine how demographic processes, particularly recruitment, may have contributed to this increase in an old-growth forest remnant, Brownfield Woods, Urbana, Illinois, U.S.A. The impact of canopy disturbance, including the outbreak of Dutch elm disease, on this increase was also evaluated. Historical maps of trees (≥7.6 cm DBH) from 1951, 1988, and 2001 in a 180 m × 280 m area were used to develop a series of univariate Ripley's L( d) functions to study changes in spatial patterns of three size classes of A. saccharum over time. Bivariate Ripley's L( d) functions were also utilized to evaluate spatial associations between recruitment and canopy disturbance. Our results indicated that A. saccharum was aggregated at most spatial scales up to 80 m during 1951–2001. Such aggregation arose mainly from small individuals. Furthermore, newly recruited individuals were aggregated at multiple spatial scales, and were significantly associated with canopy disturbance in general, as well as gaps created by Ulmus trees killed by Dutch elm disease. The aggregation of the 1951 initial group of small individuals changed via mortality to a random distribution over time. The results indicate that tree deaths caused by disturbances of different scales and types were the main cause of increased recruitment of A. saccharum in Brownfield Woods. The occurrence of Dutch elm disease further accelerated its population increase. This study demonstrated a direct spatial link between recruitment of A. saccharum and disturbance, and provided a long-term case study of a population explosion.

Soil magnetic susceptibility reflects soil moisture regimes and the adaptability of tree species to these regimes

Flooded, saturated or poorly drained soils are frequently anaerobic, leading to dissolution of the strongly magnetic minerals, magnetite and maghemite, and a corresponding decrease in soil magnetic susceptibility (MS). In this study of five temperate deciduous forests in east-central Illinois, USA, mean surface soil MS was significantly higher adjacent to upland tree species (31 × 10 −5 SI) than adjacent to floodplain or lowland tree species (17 × 10 −5 SI), when comparing regional soils with similar parent material of loessal silt. Although the sites differ in average soil MS for each tree species, the relative order of soil MS means for associated tree species at different locations is similar. Lowland tree species, Celtis occidentalis L., Ulmus americana L., Acer saccharinum L., Carya laciniosa (Michx. f.) Loud., and Fraxinus pennsylvanica Marsh. were associated with the lowest measured soil MS mean values overall and at each site. Tree species’ flood tolerance rankings increased significantly, as soil MS values declined, the published rankings having significant correlations with soil MS values for the same species groups. The three published classifications of tree species’ flood tolerance were significantly correlated with associated soil MS values at all sites, but most strongly at Allerton Park, the site with the widest range of soil drainage classes and MS values. Using soil MS measurements in forests with soil parent material containing similar initial levels of strongly magnetic minerals can provide a simple, rapid and quantitative method to classify soils according to hydric regimes, including dry conditions, and associated plant composition. Soil MS values thus have the capacity to quantify the continuum of hydric tolerances of tree species and guide tree species selection for reforestation.

Decomposition Rates of Salamander (Ambystoma Maculatum) Life Stages and Associated Energy and Nutrient Fluxes in Ponds and Adjacent Forest in Southern Illinois

Amphibian populations comprise a large fraction of vertebrate biomass in many freshwater and terrestrial ecosystems where they produce organic matter in the form of egg clutches and carcasses. A lack of quantitative information on the decomposition of these materials for any species precludes an accurate assessment of energy and nutrient fluxes from amphibians to detrital food webs and comparisons among taxa and systems. We estimated decay rates (−k) of Spotted Salamander (Ambystoma maculatum) egg clutches and larval and adult carcasses, and then used this information to estimate C and N fluxes associated with ambystomatid assemblages in breeding ponds. We found that all life stages represent a high quality source of organic matter (range C∶N = 3.7∶1–5.3∶1) in aquatic and terrestrial habitats, particularly in ponds where egg clutches and larvae are seasonally abundant. Decay rates for egg clutches (−k = 0.075 d−1), larval carcasses (−k = 0.758 d−1), and adult carcasses (−k = 0.062 d−1) were more rapid compared to published estimates for other types of animal matter in similar habitats and were much more rapid than estimates for detritus of dominant species of vegetation found in breeding ponds and adjacent forest in southern Illinois. For five regional breeding ponds, we estimated that mortality of larval A. maculatum provided a flux to detrital food webs ranging from 34.6–165.1 mg C m−2 d−1 and 6.6–31.5 mg N m−2 d−1 during decomposition; fluxes associated with egg clutches ranged from 38.8–895.0 mg C m−2 d−1 and 10.4–239.3 mg N m−2 d−1. Our study suggests that ambystomatid salamanders seasonally provide appreciable inputs of labile materials to detrital food webs and facilitate the rapid recycling of energy and materials within breeding ponds and between ponds and adjacent forest.

Making the Case for Fire in Southern Illinois Forests

Abstract Fire´s importance in the development and maintenance of oak forests has been well established across much of the eastern deciduous biome. Twentieth century fire suppression has resulted in decreased oak regeneration and portends the loss of keystone species across many landscapes including the Ozark and Shawnee Hills of southern Illinois. Here, cultural burning and harvesting fostered consistent oak recruitment until the 1950s when cutting declined and fires were widely suppressed. Now, many mature oak stands are in jeopardy of being replaced en masse by mesophytic species. We review evidence for fire as an ecosystem process and discuss an emerging strategy for the widespread reintegration of fire management across the midwestern landscape against the backdrop of media-driven public perceptions.

Energy flow and subsidies associated with the complex life cycle of ambystomatid salamanders in ponds and adjacent forest in southern Illinois

Breeding adults and metamorphosing larval amphibians transfer energy between freshwater and terrestrial ecosystems during seasonal migrations and emergences, although rarely has this been quantified. We intensively sampled ambystomatid salamander assemblages (Ambystoma opacum,A. maculatum, and A. tigrinum) in five forested ponds in southern Illinois to quantify energy flow associated with egg deposition, larval production, and emergence of metamorphosed larvae. Oviposition by female salamanders added 7.0-761.4 g ash-free dry mass (AFDM) year(-1) to ponds (up to 5.5 g AFDM m(-2) year(-1)). Larval production ranged from 0.4 to 7.4 g AFDM m(-2) year(-1) among populations in three ponds that did not dry during larval development, with as much as 7.9 g AFDM m(-2) year(-1) produced by an entire assemblage. Mean larval biomass during cohort production intervals in these three ponds ranged from 0.1 to 2.3 g AFDM m(-2) and annual P/B (production/biomass) ranged from 4 to 21 for individual taxa. Emergent biomass averaged 10% (range = 2-35%) of larval production; larval mortality within ponds accounted for the difference. Hydroperiod and intraguild predation limited larval production in some ponds, but emerging metamorphs exported an average of 70.0+/-33.9 g AFDM year(-1) (range = 21.0-135.2 g AFDM year(-1)) from ponds to surrounding forest. For the three ponds where larvae survived to metamorphosis, salamander assemblages provided an average net flux of 349.5+/-140.8 g AFDM year(-1) into pond habitats. Among all ponds, net flux into ponds was highest for the largest pond and decreased for smaller ponds with higher perimeter to surface area ratios (r2 = 0.94, P<0.05, n = 5). These results are important in understanding the multiple functional roles of salamanders and the impact of amphibian population declines on ecosystems.