. ~· I 'r MANAGEMENT PLAN PARTS I AND II Shiawassee National Wildlife Refuge 6975 Mower Road Saginaw, Michigan .Approval: l ' • CONTENTS Page I. Pa.rt I: Background Informatton....................... l II. Part II: Ob,ject:L ves ;;mel Management Strategy Ob.j ecti ves. 5 Table 1. Refuge Ob.jecti ves Swmnary............ 7 Table 2. Five-year Output Production History~ 1979 - l98J.......................... 8 Table J, Comparison of Average, Objective, and Current (1983) Output Levels ......... 9 Management Strategy ................................. 10 Figure l. NWR Location Map Figure 2. Shiawassee National Wildlife Refuge Map ', page l I I PAHT I - Background Information l. Location: Shiawassee National Wildlife Refuge is located in the central port:i.on of M:i.ch:i.ean's lower peninsula, Saginaw County,, near the south end of Saginaw Bay. The north boundary of the refuge ad,ioins the south botmdary of the City of Saginaw. It is in the tenth U. S. Congressional District of Mi.ch:Lgan. The Mich:Lgan bland:_; NWH and W,yandotte Islandf; NWH are also ad.rnin­ j_stered by Shiawr.1ssee NIVH. I.ocat:i.ons are shown on the map, Figure l. 2. History: From tlle pain L of view of an archaeologist, the Shiawa::;see Flats displayed a great potcnUal for human subsistence frmctions. Not only did the river system radiating from this area present natural avenues for transit and trade but a transition zone between upland and lowland faW1al and floral types existed as well. Thj.s intersection of well-drained up­ lands and the marshes of the Shiawassee Flats must have presented a prolific subsistence resource base for native populations. A number of specific archaeological sites have been excavated in the vicinity of the Flats. Most important of these has been the Schultz site located near Green Point Nature Center at the confluence of the Shiawassee and Tittabawassee Rivers. Others include the Andrews and Stroebel sites on the Tittabawassee River, the Schmidt site on the Cass River, and the Hodges site on the Flint River. During the period between 1870 - 1910 the Saginaw VaJ.ley was the center of timber operations in lower Michigan. The various tributaries in the Sagi­ naw Hiver watershed carried logs to sawmills located throughout the valley. As the mixed stands of deciduous and .coniferous trees were logged from the valley, agricultural development expanded on cleared land. Because o.f the lower levels and wet conditions of the Shiawassee Flats area, little farrmng development occurred until about 1925. It then became apparent that the vast areaG of ma.rsrl grar.~::;e:::, which up i.o tlwt i"J.me hnd provided excel­ lent waterfowl habitat, could be cleared, plowed, and farmed when water levels would permit. In time, farmers in this marginal area began construc­ ting open ditches to improve drainage and by 1940 many protective dikes had been built. Since that time there have been continous improvements to dikes, ditches, drainage tile, and pumping stations to alleviate flood problems and expand cultivation areas. The Shiawassee NWR was established as part of a dedicated wildlife area in the floodplain area of central Saginaw County. The area consists of two operating units, the Shiawassee NWR administered by the U. S. Fish and Wild­ life Service; and the Shiawassee River State Game Area administered by the Michigan Department of Natural Resources. These units consist of approxi­ mately 9,000 acres each and share the primary objective of providing a major resting and feeding area for migratory waterfowl. Establishment of the Shiawassee project was authorized by the N!igratory Bird Conservation Com­ mission and the Michigan Conservation Commission in March 1953. The Shia­ wasf::ee Flats and nearby Saginaw Bay of Lake Huron have been historically important waterfowl concentration points. The substantial decrease in natural marsh habitat due to land use changes (i.e. agricultural, indus­ trial, and residential developments) forced waterfowl into more restricted flight lanes. These factors, together with increasing hrmting pressure, page 2 .. ' have changed the traditional habits of migratory waterfowl and forced many species lnto southern wintering areas too early each fall and caus~d winter food supplies there to be prematurely exhausted. The chief objective of the Sl1iawassee effort was to retard· this early southward migration for sev­ eral weeks each fall. Initial management plans also provlded for food sup­ plies to be left for use during the spring migration to improve the physical c:ond:i:L:i.on of breeding b:i.rd::; Lliat are returning to ne:JL:i.ng ground:::. Shiawassee NWR was acquired with funds primarily derived from federal duck stamp sales while the StaLe Game Area lands were acquired with ftmds avail­ able from the Pittman-Robertson Act supplemented by State hunting license receipts. Wyandotte NWR was established by an act of Congress, Aueust 3, 1961, to "be maintained as a refuge and breeding place for migratory birds and other wildlife". It consists of two islands, Grassy and Mammy Juda or Marrunajuda, and adJacent shallow water areas approximately to the six-foot contour denth in the Ietroi t River just offshore from the cities of Wyandotte and Ecorse. Total acreage is approximately 304 acres. From 1948 to 1961 the islands were utilized by the U. S. Coast Guard. The Mlchigan Islands NWE was established by Executive Order 93.34 on April 21,, 191,3 as a refuge and breeding ground for migratory birds and other wUclli.fe. The~;e three :i:::land;;:: Shoe and Pismire in Lake Michigan and Scare­ crow in Lake Huron are 2, J, ::md 7 acres in size and are similar in charac­ ter. In 1965 a fourth island, Thunder Bay, was added to the refuge by the U. S. Coast Guard tmder a revocable permit (five-year renewal periods). The Service has secondary jurisd:i.ction on 121 acres of the total 168 acres at Thunder Bay Island. Gull Ir.~land ( 230 acres) became the fifth island in the syr.;tem in 1969 when it w::_1;3 ceded to the Service by the U. S. Coast Guard. The three or:i.ginal "i.:=;lnncls j n the MiehJgan Islands NWR. were desienated as Wilderness Areas in 1970 under Public Law 91-504, Stat. 1104. 3. Environment: Shiawassee NWR, a portion of an area known locally as the Shiawassee Flats, has a contributing drainage area of approximately 6,060 square miles (10.6 percent of the State of Michigan). Four rivers converge in the Shiawassee NWR accounting for the majority of the contributing drain­ age a.rea. These rivers, along with their drainage area at the nearest USGS gage, are as follows: the Tit tabawassee with a 2, L,OO square mile drainage at gage on river mile 23; the Flint with a 1,200 square nule drainage at gage on river mile 12; the Cass with an 850 square mile drainage at gage on river mile 17, and the Shiawassee with a 640 square mile drainage at' gage on river mile 14. In addition to the four main tributaries there are sever~ al smaller streams which enter the Shiawassee River within or just upstream of the refuge. The larger of these are the Bad River draining 248 square miles, Misteguay Creek draining 137 square miles, and Swan Creek draining 127 square miles. At the northeastern edge of the Shiawassee NWR, at the confluence of the Tittabawassee and Shiawassee Rivers, the Saginaw River proper begins. The Saginaw H~.ver, 22 miles long, flows northerly from this point tl1rough the dties of Saginaw and Bay City to discharge into Saginaw Day, an arm of Lake Huron. Topography on the Slliawar:>see NWH is flat and generally ranges from 580 to 590 feet m.s.l. Flooding of the refuge area occurs often due to the in­ ability of the Saginaw Ri.ver to carry the full load of runoff from the page J various tributary rivers. Flooding may be compounded by ice blockage of the various river channels during late winter breakup. Water level elevations in the Saginaw Bay also have a heavy :influence on flooding events in the refuge area. Bay water levels are influenced by winds which may change water level elevations by four feet or more. The average water level in Saginaw Bay :is 579.5 feet m.s.l.; however, deviations above and below that level are the rule rather tl1a.n the exception. Although water level fluctua­ tions from these "wind tides" are not of as high a magnitude on the refuge as on the Bay, day to day changes of one or two feet are quite common. The combination of high Bay water levels and high river discharges occurring concurrently poses the greatest threat of flooding. Precipitation in the Shiawassee NWR area is relatively well distributed an­ nually with the maximum ammmts occurring in summer ( JO. 39" average annual precipitation). July temperatures average in the low seventies while Janu­ ary temperatures are in the low twenties. Snowfall averages about 46 in­ che~~ annually. Weather conditions at Wyandotte NWR are similar to Shiawas­ see while the Michigan Islands NWR experiences cooler temperatures and more severe winters. L.. Resources: Habitat types and acreages are roughly as follows: National Wildlife Refuge Habitat Type Shiawassee Michigan Islands Wyandotte Seasonally flooded basins or flats 10 50 Shallow fresh marshes 100 40 20 Deep fresh marshes 1,200 20 Open fresh water 184 Rivers and streams 400 Other - moist soil 1.mits 600 Croplands 1,700 Grasslands 500 Non-commercial forests 4,100 250 Brush 150 20 Rocks 10 Sands 53 10 Aclministrat:i. ve lands 234 TOTAL ....... 8,984 J6J 304 -)(·Figure 2 gives a map showing prevalent habitat types on Shiawassee NWR.