Monitoring Bird, Fish, and Vegetation Communities at Prime ...Vegetation Community Response METHODS •Salt Marsh Integrity (SMI) and Saltmarsh Habitat and Avian Research Program (SHARP)

Susan GuiterasSupervisory Wildlife Biologist

USFWS – Coastal Delaware National Wildlife Refuge Complex

USFWS (Refuges): Nathan Bush, Annabella Larsen, Jennifer McAndrews

USFWS (Fisheries): Steve Minkkinen, John Gill

University of Delaware: Elizabeth Tymkiw, Greg Shriver, Tim Freiday, Mac McGraw

DNREC: Lyndie Hice-Dunton, Bob Scarborough, Andrew Howard, Alison Rogerson, Drexel Siok, Kenneth Smith

Monitoring Bird, Fish, and Vegetation Communities

at Prime Hook NWR Before, During, and After Tidal Marsh Restoration

10,000 acres, mostly wetlands

Two central units – Unit II and Unit III – managed as freshwater impoundments for waterfowl habitat through installation of water control structures in 1980’s

Impoundment management successful until series of storms created breaches in Unit II shoreline

Hurricane Sandy brought largest final blow to the system

Rapid peat collapse and extensive conversion to open water in Unit II and Unit III

Tidal Marsh Restoration

Prime Hook NWR

Largest tidal marsh restoration project in the east at ~4000 acres

Based on extensive hydrodynamic modeling with local data

SHORELINE RECOVERY

Closure of large breaches

Restoration of 8900 ft of shoreline, dune, and back barrier platform

MARSH RESILIENCY

Dredged ~25 miles of interior tidal channels in Unit II and Unit III

Remove WCS, DelDOT bridge

Thin layer deposition on site

Tidal Marsh Restoration

Comprehensive Biotic & Abiotic Monitoring Program Cooperative Agreement with DNREC

Coastal Programs / DNERR Wetland Assessment

University of Delaware Chris Sommerfield, Tom McKenna,

Greg Shriver, Chris Williams

USFWS Maryland Fish & Wildlife Conservation Office USFWS Northeast Regional I&M and LMRD staff Refuge staff USGS Rutgers University

Monitoring our Progress

Biological Monitoring Overview

• 15-20 Bird & Vegetation Survey Points in each unit

• Unit I (north) and Unit IV (south) serve as reference areas

• Fish survey locations varied, focused at WCS and in channels

Vegetation Community Response

METHODS

• Salt Marsh Integrity (SMI) and Saltmarsh Habitat and Avian Research Program (SHARP)

• 50-meter radius around bird survey points

• Community cover types and dominant species

• Point-intercept transect (100 meters long)

• Photopoints (North, East, South, West)

• Mid-Atlantic Tidal Rapid Assessment Method (MidTRAM)

• Habitat Attribute: Bearing capacity, horizontal vegetation obstruction; Also - biomass, RTK elevation

• NVDI (Normalized Difference Vegetation Index)

• Open Water : Vegetated Marsh ratio from imagery


RESULTS / HIGHLIGHTS - SMI / SHARP / MidTRAM

• No in-depth analysis of vegetation community data yet

• Above- and below-ground biomass collected pre-restoration and will be repeated after a few growing seasons

• Changes in bearing capacity and local elevation depend on presence (or not) of dredged material deposition

• Resurgence of marsh vegetation along the periphery of both units, and in areas of deposition following dredging

• Photopoints currently most compelling data



Pluchea odorata(Saltmarsh fleabane)

Leptochloa fascicularis(bearded sprangletop)

Spartina alterniflora(Saltmarsh cordgrass)

Eleocharis parvula(dwarf spikerush)

Echinochloa crus-galli(barnyardgrass)


Dredged channel and thin-layer deposited material


Planted back-barrier platform


Many areas still show little change – yet!


RESULTS / HIGHLIGHTS – NVDI

• “Hot off the Press”

• Preliminary results, not closely examined yet

• Different imagery sources (USDA NAIP vs DigitalGlobe WorldView3)

• Tide timing not controlled

• In restoration units, % open water starting to drop

• Unit I had also been affected by increase in flooding and ponding

Total Unit

Acres

2015 % Open

Water

2016 % Open

Water

2015 2016 2015 2016

Unit I (East) 805 255 178 550 628 32% 22%

Unit I (West) 851 133 78 718 773 15% 9%

Unit II 1438 1249 996 189 442 87% 69%

Unit III 2335 1504 1299 830 1036 64% 56%

Open Water

(acres)

Vegetated Marsh

(acres)


• Some large areas in Unit III adjacent to dredged channels, where material has been sidecast, filled in substantially


• Planted vegetation in back barrier area is evident (dune not included in analysis)


• Creek coves in western Unit II filling back in as water levels drop following breach closure

• Cods Rd example at the end of previous talk (Scarborough)

Bird Community Response

METHODS

• Salt Marsh Integrity (SMI) and Saltmarsh Habitat and Avian Research Program (SHARP)

• 15-20 bird survey points per unit (including adjacent salt marsh units as reference)

• 5-minute passive point count followed by secretive marshbirdcallback sequence

• 3 visits per year (usually)

• Ultimately… Tidal Marsh Obligate (TMO) analysis

• Beach nesting birds

• Routine surveys in partnership with refuge volunteers and state DNREC staff

• Nest monitoring and protection

• Integrated Waterbird Management & Monitoring (IWMM)

• Year-round routine roadside surveys by refuge staff


RESULTS / HIGHLIGHTS – Saltmarsh Birds (SMI/SHARP)

Unit II Shoreline Recovery

(Not surveyed)

(Not surveyed)

(Not surveyed)


Shorebird increase on newly created mudflats in both units


RESULTS / HIGHLIGHTS – Beach-nesting Birds

First ever documented Piping Plover nest on the refuge.

Unfortunately, not successful, but a great start

Can you spot the eggs?


RESULTS / HIGHLIGHTS – Beach-nesting Birds

Most “robust” least tern(LETE) colony in the state for years• Peak numbers over

100 birds• Close to 20 nests• Successfully fledged

at least 3 young

American oystercatchers (AMOY) nested but were not successful

All together now… “Awwwww!”

Horseshoe Crab Response

RESULTS / HIGHLIGHTS – Horseshoe Crab Spawning

More horseshoe crabs than expected in first year!

Pre-restoration surveys were not quite in the same area (further north on existing un-restored beach), but will be a useful reference for comparison

Fish Community Response

METHODS

• Seasonal fish community surveys

• 2014 (Summer, Fall); 2015 (Spring, Summer, Fall); 2016 (Spring, Summer)

• Fyke nets, Seine nets, Clover traps (varied as restoration progressed)

• Acoustic tags deployed to see how diadromous fish are using the system prior to, during, and after restoration

• 8 receiver sites (11 in 2015)

• Tag data downloaded seasonally (more often at first), data comes from other researchers in the network as well

Fish Community Response

RESULTS / HIGHLIGHTS – Fish Community Surveys

• Results thus far still being summarized

• Species that increased:

• White perch

• Sheepshead minnow

• Black drum

• Species caught 2016 not detected previously:

• Atlantic croaker

• Diamondback terrapin

• Species that decreased:

• Common carp

• Killifish spp

• Silverside spp

• Mummichog

PRE-RESTORATION• Many fish not detected after <2 months – mortality, moved out of range, missed detection?• Only one fish documented moving through breach (2014-2015, before closure)• Evidence of fish emigrating out of refuge through both north and south routes• Limited documentation of fish moving through freshwater creeks• Several fish detected outside of refuge (one alewife turned up in NJ!)

Several different tagging efforts between Sept 2014 – Nov 2016

139 acoustic tags out

Species Acoustic Tags

Floy/ PIT tags

Total

American eel

49 56 105

White perch

83 514 597

Alewife 7 0 7

Striped bass

0 1 1

Ongoing Monitoring

• Post-restoration monitoring will continue

• Partnerships funded at least in part until 2019

• Applied for Hurricane Sandy funding for longer term monitoring

• Some monitoring will be the “new order of business” for refuge biology program

Thank You! Any Questions?

Behind the Scenes

• Laura Mitchell

• Curtis George

• Mike Mensinger

• Zac Duval

• John Biddle

• Drexel Siok

• Christina Whiteman

• Kenny Smith

• Andrew Howard

• Alison Rogerson

• Katie Bell

• Chris Townsend

• Collin Thomas

• Rodrick Murray

• Melissa Vorn

Documents

Monitoring Bird, Fish, and Vegetation Communities at Prime ...Vegetation Community Response METHODS •Salt Marsh Integrity (SMI) and Saltmarsh Habitat and Avian Research Program (SHARP)