Title Genres Topics Date (Start) Date (End)
Breeding bird survey, 1976 Checklists Bird watching Birds--Breeding Birds--Research Ornithology--Methodology N/A N/A
Robert Jessen letter and checklist to Vernon M. Kleen regarding winter birds sighted in Mahaska County, April 2, 1975 Checklists Correspondence Field notes Bird watching Birds--Identification Birds--Research Ornithology--Methodology 1975-04-02 N/A
Robert Jessen letter and checklist to Vernon M. Kleen regarding birds sighted during 1974 fall migration, December 1, 1974 Checklists Correspondence Bird watching Birds--Identification Birds--Migration Birds--Research Ornithology--Methodology 1974-08-01 1974-11-30