Wood Storks & Wetlands. UCF Jan. 26, 2010 Jason Lauritsen Asst. Director Corkscrew Swamp Sanctuary

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1 Wood Storks & Wetlands UCF Jan. 26, 2010 Jason Lauritsen Asst. Director Corkscrew Swamp Sanctuary

2 Stork Overview 1984 on Endangered Species List South Carolina, Georgia, Alabama & Florida Mature at 3-4 years Feeds by touch Nests in colonies (cypress, mangrove, other) Feeds on fish & invertebrates 1 st year critical, may live 11+ years Can fly (soar) over 50miles from nest to feed

3 Nesting Range Wood Stork Overview Feeding Survival

4 Population History Prior to the 1970 s about 70% of US storks nested in South Florida Total nests in US: 1930 s ~ 20,000 pairs 1960 s ~ 10,000 nesting pairs Late 70 s ~ 5000 nesting pairs

5 USFWS 5-year Status Review Sept. 28 th 2007 recommended upgrading status from Endangered to Threatened Northern/coastal range is stable or improving Southern range is unstable

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7 Wood Stork Nesting at Corkscrew Nest Numbers Year No. of Nesting Pairs No. of Birds Fledged

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9 Core Foraging Area (18.6 miles)

10 Wood Stork Nesting at Corkscrew Nest Numbers Year No. of Nesting Pairs No. of Birds Fledged

11 1961 & 1966 ~ 6000 pairs nested at Corkscrew ~2.6 million lbs of fish to supply those nests (440lbs/nest)

12 Loss of about 35% of wetlands in S. Florida

13 Nature of Historic Wetland Losses: Roads & Canals Resource Inventory and Analysis, Big Cypress National Preserve. Vol

14 Historic development pattern in SWFL Avoided deep wetlands Drain shallow wetlands (ditches/canals/lakes) Build in shallow wetlands

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22 Wetland Losses within the CFA From pre-development to 2004 Total 44% Short hydroperiod 62% (73-52%)* Long hydroperiod 19% (34-7%)* Tidal 10% *not all wetland data from the 2004 Land Cover map had hydroperiod data.

23 How do they work? Flat topography Rainy season Dry season cycle Floods, droughts, hurricanes, fires

24 hydric pine flatwoods wet prairie cypress deep marsh 1-2 months, 6 inches 2-6 mo.12 in. 6-8 mo. 18 in mo. 24 in. September December March

25 Gator holes act as dry season refuges for aquatic fauna

26 South Florida dry-season & Stork nesting Storks arrive in October Should start nesting in Nov/Dec Storks wait for foraging sites to recede to 2-16 Storks need a 4 months window for nesting success Loss of Oct-Dec wetlands shifts foraging later in year

27 Productivity decline preceded shift in nest timing. Since 1979 storks only nest early during hyper-wet years

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29 Audubon Research Wood stork foraging habitat assessment for SWFL Foraging locations Aerial surveys, follow-flights GPS tags on nesting storks Foraging quality Prey sampling Will lead to growth tools & policy recommendations

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31 Satellite tagged storks: 5 tagged birds in area 4 nesting at Corkscrew One bird from SWA colony 5 more tags to deploy Position data: Habitat use data 18 positions/day Multiple years Enhance follow-flights Establish C.F.A.

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33 Oct 06 Jan 07 Feb June 07

34 Stork habitat use in SWFL Early nesting season - few natural feeding sites remain, often forage in altered locations - ditches, ag fields etc. Mid-late nesting season - majority of foraging sites in natural wetlands

35 Habitat Use Corkscrew B-staff gauge Water Level (ft. NGVD 29) /1/05 2/1/05 3/1/05 4/1/05 5/1/05 6/1/05 7/1/05 8/1/05 9/1/05 10/1/05 11/1/05 12/1/05 1/1/06 2/1/06 3/1/06 4/1/06 5/1/06 6/1/06 7/1/06 8/1/06 Date

36 Oct Dec. foraging Ditches, lake edges, canals, stormwater ponds

37 Wood Stork Foraging along Corkscrew Road Photo taken 10/17/08 Photo taken 10/17/08 Photo taken 11/18/08

38 Foraging Wood Storks on RCH mine photos taken on wood storks documented foraging in these ditches, in 1 event

39 Oct-Dec. Foraging in Ag WOST foraging Assessment

40 Mid-late season foraging Cypress, donut holes, open marsh

41 Storks are routinely foraging in forested wetlands

42 Development in SWFL

43 Future stork population trends in South Florida: If they initiate nesting early (Nov.-Dec) 28% increase over next 30 years If they continue to nest late (late Jan-Mar.) 38% decrease over next 30 years Unpublished study by Rena Borkataria, U of F

44 In a Nutshell SWFL s wood stork colonies are increasingly at risk We ve lost & continue to lose too many shallow wetlands this makes storks nest later in the year To stabilize or recover them we need to restore/protect these shallow wetlands (used by storks from Oct.- Jan.)

45 Special Thanks to: Ed Carlson Brad Cornell David Ceilley Ann Marie Lauritsen Mike Duever Mike Knight Shawn Liston USFWS SFWMD Beaver Aviation Ralph Arwood Larry Bryan Rena Borkhataria