MADISON, Wis. (AP) – Wisconsin wildlife officials are urging outdoor enthusiasts to sign up for nature field trips this summer and fall.  The Department of Natural Resources and the Natural Resources Foundation are offering the trips. The schedule includes a Mississippi River eagle boat cruise and fawn collaring in Outagamie County in May, a stream ecology outing at Black Earth Creek in Dane County in June, a northwestern Wisconsin wetlands tour in August and bat observations in Dodge County in August or September.  A complete listing of trips is available on the Natural Resources Foundation’s website. The trips are marked to indicate their physical demands.  Current foundation members can sign up starting March 20. People can join the foundation before then can take advantage of the early sign-up. Public registration begins after April 1.