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Declines in bumble bee species range and abundances are documented across multiple continents and have prompted the need for research to aid species recovery and conservation. The rusty patched bumble bee (Bombus affinis) is the first federally listed bumble bee species in North America. We conducted a range-wide population genetics study of B. affinis from across all extant conservation units to inform conservation efforts. To understand the species' vulnerability and help establish recovery targets, we examined population structure, patterns of genetic diversity, and population differentiation. Additionally, we conducted a site-level analysis of colony abundance to inform prioritizing areas for conservation, translocation, and other recovery actions. We find substantial evidence of population structuring along an east-to-west gradient. Putative populations show evidence of isolation by distance, high inbreeding coefficients, and a range-wide male diploidy rate of ~15%. Our results suggest the Appalachians represent a genetically distinct cluster with high levels of private alleles and substantial differentiation from the rest of the extant range. Site-level analyses suggest low colony abundance estimates for B. affinis compared to similar datasets of stable, co-occurring species. These results lend genetic support to trends from observational studies, suggesting that B. affinis has undergone a recent decline and exhibit substantial spatial structure. The low colony abundances observed here suggest caution in overinterpreting the stability of populations even where B. affinis is reliably detected interannually. These results help delineate informed management units, provide context for the potential risks of translocation programs, and help set clear recovery targets for this and other threatened bumble bee species., (© The Author(s) 2024. Published by Oxford University Press on behalf of Entomological Society of America.)

Vector-borne disease prevalence is increasing at a time when surveillance capacity in the United States is decreasing. One way to address this surveillance deficiency is to utilize established infrastructure, such as zoological parks, to investigate animal disease outbreaks and improve our epidemiological understanding of vector-borne pathogens. During fall 2020, an outbreak of epizootic hemorrhagic disease (EHD) at the Minnesota Zoo resulted in morbidity and seroconversion of several collection animals. In response to this outbreak, insect surveillance was conducted, and the collected insects were tested for the presence of epizootic hemorrhagic disease virus (EHDV) by RT-qPCR to better understand the local transmitting vector populations responsible for the outbreak. Six pools of Culicoides biting midges were positive for EHDV, including three pools of Culicoides sonorensis , two pools of Culicoides variipennis , and a pool of degraded C. variipennis complex midges. All three endemic serotypes of EHDV (1, 2, and 6) were detected in both animals and midge pools from the premises. Despite this outbreak, no EHDV cases had been reported in wild animals near the zoo. This highlights the importance and utility of using animal holding facilities, such as zoos, as sentinels to better understand the spatio-temporal dynamics of pathogen transmission.

Recognizing the imperative to evaluate species recovery and conservation impact, in 2012 the International Union for Conservation of Nature (IUCN) called for development of a "Green List of Species" (now the IUCN Green Status of Species). A draft Green Status framework for assessing species' progress toward recovery, published in 2018, proposed 2 separate but interlinked components: a standardized method (i.e., measurement against benchmarks of species' viability, functionality, and preimpact distribution) to determine current species recovery status (herein species recovery score) and application of that method to estimate past and potential future impacts of conservation based on 4 metrics (conservation legacy, conservation dependence, conservation gain, and recovery potential). We tested the framework with 181 species representing diverse taxa, life histories, biomes, and IUCN Red List categories (extinction risk). Based on the observed distribution of species' recovery scores, we propose the following species recovery categories: fully recovered, slightly depleted, moderately depleted, largely depleted, critically depleted, extinct in the wild, and indeterminate. Fifty-nine percent of tested species were considered largely or critically depleted. Although there was a negative relationship between extinction risk and species recovery score, variation was considerable. Some species in lower risk categories were assessed as farther from recovery than those at higher risk. This emphasizes that species recovery is conceptually different from extinction risk and reinforces the utility of the IUCN Green Status of Species to more fully understand species conservation status. Although extinction risk did not predict conservation legacy, conservation dependence, or conservation gain, it was positively correlated with recovery potential. Only 1.7% of tested species were categorized as zero across all 4 of these conservation impact metrics, indicating that conservation has, or will, play a role in improving or maintaining species status for the vast majority of these species. Based on our results, we devised an updated assessment framework that introduces the option of using a dynamic baseline to assess future impacts of conservation over the short term to avoid misleading results which were generated in a small number of cases, and redefines short term as 10 years to better align with conservation planning. These changes are reflected in the IUCN Green Status of Species Standard., (© 2021 The Authors. Conservation Biology published by Wiley Periodicals LLC on behalf of Society for Conservation Biology.)

Residual renal function is an important parameter int he design of dialysis regimens. In this study residual renal clearance of potential uremic toxins in the middle molecular weight range (originally thought to be 300-2000 daltons, but now considered close to 300-700 daltons) was investigated in patients with predialysis chronic renal failure. Middle molecules were isolated from uremic sera and urines by gel filtration and further separated by gradient elution chromatography to give 7 to 8 definable uremic middle molecular weight species. The renal clearances of middle molecule fractions were compared with simultaneously measured endogenous creatinine, urinary inulin and single short inulin clearance. The four middle molecule fractions which were quantitated (7a, b, c and d) were found to be freely filtered and to have renal clearances in end stage renal failure approximately equal to the endogenous creatinine clearance. Thus, renal handling of middle molecules is strikingly different from that of other peptides of peptide hormones in that the species do not appear to be catabolized, secreted or reabsorbed by the renal tubules to any significant degree.

Renal handling of uremic middle molecules (MW 300-2000 daltons) was investigated (1) in the diseased kidney in nine patients suffering from chronic renal failure in the pre-dialysis phase, and (2) in the isolated perfused rat kidney using hemofiltrate and albumin (5 gm/100 ml) containing perfusate. Middle molecules clearances are compared to the simultaneously measured inulin and creatinine clearances. Four middle molecule fractions (peak 7a, 7b, 7c, and 7d) were quantitated after high-speed gel filtration and gradient elution chromatography and found to be freely filtered (= middle molecules clearances not differing from inulin and creatinine clearances) in uremia in man. In the "intact" (isolated perfused) rat kidney, elimination also takes place by glomerular filtration (peak 7a, 7c at high perfusate levels). Peaks 7b and 7d are slightly reabsorbed (15% and 25%, respectively, of filtered load), whereas 7c1 is secreted up to 220% of inulin clearance at low perfusate levels. No renal catabolism and high urinary excretion of middle molecules clearly indicate different renal handling of this species in comparison to other peptides or peptide hormones of the same molecular weight range.