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Conservation practitioners often rely on captive breeding programs to supplement wild populations at risk of extinction. While supplementation has been successful for some taxa, the success of using hatchery fish to supplement wild populations is severely impacted by predation. Elevated predation on hatchery fish may arise because hatchery environments often differ from wild environments and constrain the ability of hatchery fish to be adapted to the environments in which they are released. We assessed the effects of abiotic enrichment on the expression of behavioral and morphological phenotypes across three populations of a species of conservation concern, the Arkansas darter (Etheostoma cragini). We also used a factorial approach to assess whether abiotic enrichment and predator training increases survival during encounters with a novel predator. We found that abiotic enrichment affected ecomorphological attributes associated with fins; generally, measures of the caudal and pectoral fin decreased in the treatment group compared to the control treatment. Behaviorally, darters reared with abiotic enrichment increased feeding and decreased movement compared to the control group. Importantly, we found that in combination with predator training, abiotic enrichment increased the probability of surviving first encounters with a predator. We therefore recommend conservation practitioners incorporate abiotic enrichment and predator training in hatchery programs. Captive breeding programs are used to supplement wild populations at risk of extinction, but hatchery‐reared fish often do not survive after release. Using the threatened Arkansas darter, we show that abiotic enrichment and predator training of hatchery populations impact behavior and morphology and increase the probability of surviving first encounters with a non‐native predator. [ABSTRACT FROM AUTHOR]

Fisheries biologists have been hesitant to use passive integrated transponder (PIT) tags in small‐bodied fishes (40–200 mm TL) such as darters (Percidae: Etheostomatinae) because of the fishes' size and potential effect on swimming performance. The authors used constant acceleration trials to evaluate the swimming performance of Arkansas darters Etheostoma cragini in control (no incision or tag), sham (incision and suture) or PIT tagged (surgically implanted 8 × 1.4 mm intra‐peritoneal PIT tag) treatments. Tag retention and fish survival were monitored for up to 199 days post‐tagging. Maximum swimming velocity did not differ between control, sham and PIT tag treatments, nor was maximum swimming velocity affected by the tagging procedure. Tag retention was 100%, and the overall survival of tagged fish was 88% in the swimming study, and 100% in the long‐term study, suggesting that small PIT tags are suitable for use in darters. The authors include a brief meta‐analysis on the results reported by 20 studies that PIT tagged small‐bodied fishes, representing 38 species and nine families of freshwater fish. [ABSTRACT FROM AUTHOR]

Past experiments on sand-based putting greens have frequently used randomized complete blocked designs (RCBD), even though these experimental areas are relatively uniform with regard to external variables. Consequently, completely randomized designs (CRD) may have had better precision with which to estimate treatment effects compared with RCBD. The objective of this study was to estimate the relative efficiency (ERE) of a RCBD compared with a CRD when evaluating common parameters on sand-based putting greens. Uniformity trials were conducted in Arkansas and Nebraska on sandbased putting greens established with creeping bentgrass (Agrostis palustris Huds.). Estimated relative efficiency values were calculated for varying blocking schemes when measuring canopy temperature, soil temperature, soil moisture, clipping yield, and macronutrient content in plant tissues. Since canopy temperatures were time dependent, when those measurements were collected by a blocking scheme, the associated RCBD was approximately nine times more efficient than a CRD. For the remaining parameter and blocking scheme combinations, ERE values indicated that the precision between RCBD and CRD was similar. Therefore, it is likely that the precision with which treatment effects are estimated is not compromised from the use of RCBD on sand-based putting green trials. [ABSTRACT FROM AUTHOR]