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We conducted a series of studies to improve our understanding of pistolgrip life history and distribution in Minnesota and Wisconsin. In the St. Croix River, where this species is relatively abundant, we studied animals biweekly from May-Nov. 1997, Apr.-Oct. 1998 and nearly biweekly during May-Jul. 2004-2007 and observed gravid females between late Apr.-Jul. at water temperatures 13-25 C. Females held mature glochidia in a large mantle magazine that was significantly more inflated at night. Fifty-seven pistolgrip glochidia measured using scanning electron microscopy had an average height and length of 119 ± 6 Jam and 102 ± 4 µm (± 1 SD), respectively. Of 65 fish species (18 families) exposed to pistolgrip glochidia only flathead catfish (Pylodictis olivaris) and brown (Ameiurus nebulosus) and yellow (A. natalis) bullheads were suitable hosts, with flathead catfish showing the strongest host response. Glochidia grew 422 ± 17% while attached to fish. Pistolgrip is found in central and southeastern U.S. but is declining in several locations. Surveys conducted between 1980 and 2009 show the geographic range of pistolgrip has decreased in Minnesota and Wisconsin. It is extirpated from the Minnesota River and nearly so in the Mississippi River. However, we see evidence of a recovering population in a once heavily polluted reach of the Mississippi River downstream of Minneapolis-St. Paul. The largest populations are in the lower reaches of the St. Croix (MN, WI), Chippewa, Black, Wolf and Wisconsin rivers (WI). In light of the apparent close association between pistolgrip and flathead catfish, we recommend pistolgrip conservation efforts include sustainable flathead catfish management and habitat improvement to support expansion of remaining pistolgrip populations., INTRODUCTION 'The heavy waves will break many of the fine strings on which the young clams are fastened and wash them to the shore. Millions of such little tiny shells [...]

The ellipse, Venustaconcha ellipsiformis (Bivalvia: Unionidae), was first recorded in Minnesota from the Straight River in 1987, but we knew little of its distribution in the state, brooding behavior, glochidial host fish relationships or status. To examine these questions, we followed standard procedures to conduct an extensive, qualitative statewide mussel survey, described mantle flapping behavior from field and laboratory observations and identified suitable glochidia hosts in the laboratory and from naturally infested fishes. We found extant populations in five Mississippi River tributaries in southeastern Minnesota: the Cannon, Cedar, Root, Upper Iowa and Zumbro rivers. This appears to be the extent of its historic range in Minnesota as no valid records were found elsewhere. Among these, the largest population occurred in the headwaters of the Root River drainage, which was also the only drainage where we observed recent recruitment. Brooding V. ellipsiformis quickly flap a small mantle extension, often in response to passing shadows or jarring of the substrate, or their mantle extensions may be slowly undulated. We identified 11 fish species as suitable hosts for V. ellipsiformis glochidia in the laboratory: brook stickleback (Culaea inconstans), mottled sculpin (Cottus bairdii), slimy sculpin (C. cognatus), logperch (Percina caprodes), mud darter (Etheostoma asprigene), rainbow darter (E. caeruleum), Iowa darter (E. exile), fantail darter (E. flabbelare), Johnny darter (E. nigrum), banded darter (E. zonale) and blackside darter (P. maculata). Rainbow darter, fantail darter and blackside darter were also found naturally infested with V. ellipsiformis glochidia. Venustaconcha ellipsiformis should remain classified as a 'Threatened' species in Minnesota and management should include conserving populations within drainages due to its restricted range and likely low dispersal ability.

Land use practices have created a mosaic of habitats that in some ways resemble the presettlement prairie mosaic. To examine the effects of land use practices on habitat use by small mammals, trapping was done in native, hayed and old-field prairies in E-central Kansas. Relative abundance of all small mammals was highest in the old field and lowest in the hayfield. The high relative abundance of Sigmodon hispidus and Peromyscus leucopus in the old field may be explained by heterogeneity of vegetation, and prevalence of forbs and woody plants. Microtus ochrogaster and Blarina hylophaga had higher relative abundance in the native prairie than the other species, possibly due to higher vegetation cover. The low relative abundance of small mammals in the hayfield suggests the importance of vertical structure and canopy cover of vegetation, particularly for M. ochrogaster and S. hispidus. Land use mosaic may affect the structure and composition of small mammal communities in a fashion similar to that of the natural prairie mosaic.

We document the occurrence of freshwater mussels living on bedrock, a substrate generally considered to be unsuitable. We found 54 individuals of six species in this habitat. Our observations support the hypothesis that substrate stability is an important component of mussel habitat., INTRODUCTION Freshwater mussels may occupy a variety of substrate types (Coker et al., 1921), which has added to the difficulty in predicting their distribution and abundance at small spatial scales [...]