Ninigret National Wildlife Refuge
Northeast Region
 

Management

The following was taken from the 2008-09 Annual Habitat Work Plan, Rhode Island National Wildlife Refuge Complex. For an explanation of the larger context for the following management actions, click on this link to the national Strategic Habitat Conservation/Landscape Conservation Cooperatives.

2008 Management Actions

Piping Plover
Refuge beaches, above the high tide line, were closed to the public in early April following the guidelines in the 1996 Piping Plover Atlantic Coast Population Revised Recovery Plan. In addition, habitat on local beaches was symbolically fenced to protect nesting birds, as per the cooperative agreement with the RI Department of Environmental Management (DEM), and Memoranda of Understanding (MOUs) for these sites. All beaches were walked 2-3 times per week to locate nesting piping plovers and then monitored daily during incubation and chick rearing to document reproductive success of each pair.
Specific Actions:

  • Remote cameras were set up at Ninigret NWR and Napatree to monitor predator activity around nests.
  • We implemented predator control at Ninigret NWR and Conservation Area in an attempt to increase nest and fledge success at this site.
Least Tern
Least Tern nesting sites were surveyed two to three times per week starting in April. Active sites were roped off with symbolic fencing to prevent disturbance from vehicles and pedestrians. Nests and chicks were monitored at least two to three times per week until all chicks fledged. Nests were identified from a distance by counting incubating adults. Nesting pairs are reported in Census A (as of June 20th 2008) and Census B (highest count after June 20th 2008).
Specific Actions:
  • Remote cameras were set up at Ninigret NWR to monitor predator disturbances to the nesting colony.
  • Nesting boxes were distributed throughout the colony at Ninigret in an attempt to improve fledging success.

Habitat Restoration:

Phragmites removal at Ninigret NWR
Treatment of approximately 20 acres of salt marsh habitat at Ninigret NWR was initiated in fall of 2006 to reduce the density of common reed (Phragmites australis) in the marsh. We documented a dramatic decline in the number of live stems per plot between the pre-treatment monitoring (pre) and the initial herbicide and mulch treatments at Cards Pond and Ninigret NWR, see chart below.

Number of Common reed live stems recorded in 60 plots prior to and after herbicide and mulch treatments at Ninigret NWR and Cards Pond (adjacent to Trustom Pond NWR).
Number of Common reed live stems recorded in 60 plots prior to and after herbicide and mulch treatments at Ninigret NWR and Cards Pond (adjacent to Trustom Pond NWR).

American Black Duck Monitoring:

Winter waterfowl surveys are conducted in salt marsh habitats at Ninigret, Sachuest Point and the John H Chafee refuges. Although surveys have been conducted for over 10 years at three of the refuges, JHC surveys were first conducted in 2004. Surveys are initiated in November of each year and continue bi-weekly through February.

The average number of American Black Ducks (ABDU) observed per survey from 1998 through 2008 on four NWRs in RI.
A color bar chart showing the average number of American Black Ducks (ABDU) observed per survey from 1998 through 2008 on four NWRs in Rhode Island.

Rare plant population monitoring and management:

  • A spring burn was conducted on April 30, 2008 at 7pm, just in the interior of the rare plant site. The site was wet and consequently the burn was very ‘spotty’ and many areas did not burn. Prior to the burn it looked as though there was significant shrub growth that may interfere with rare plant populations. One strip along the eastern edge of the site was inadvertently mowed as part of a fire break. A few of the long term monitoring stakes were bent, but should still be identifiable.
  • A subset of the 61 vegetative plots that have been monitored since 1996 were monitored this year. The plots were chosen based on the presence of rare plants in earlier surveys. We compared our data collected this year to data collected in 2005 and 2006 (this is the only raw data that we have). Overall, there is a marked decrease in the number of plants observed at the chosen plots. This is displayed in the chart below – ALFA is Aletris farinosa, PLCI is Platanthera ciliaris and POCR is Polygala cruciata.
Average number of three state endangered and threatened rare plants detected per plot at the Ninigret endangered Species Area, Ninigret NWR: Color bar chart showing the average number of three state endangered and threatened rare plants detected per plot at the Ninigret endangered Species Area, Ninigret NWR

Invasive Plant Management

This year (2008) at Ninigret, volunteers spent approximately 53 hours hand pulling non-native invasive plants along the trails and in the regenerating runways. This has facilitated the transition of these habitats to a mix of native shrub and grass species.

Response of the Resources of Concern

  • Christmas bird counts were conducted in grassland habitats at Sachuest Point, Trustom Pond and Ninigret by volunteer birders. All of the sites continue to provide valuable habitat for a wide diversity of species throughout the winter months, including short-eared owl, northern harrier, and eastern meadowlark.
  • Woodcock surveys have been conducted intermittently over the last 15 years at Ninigret and Trustom. There are two survey routes at Trustom for a total of 12 points and one route at Ninigret consisting of 9 points. We have data for 1993-1995, 2006 and 2008 (see chart below).
  • Average number of American woodcock detected per point during spring calling surveys at Trustom Pond and Ninigret NWRs during the last five years. Color line chart showing the average number of American woodcock detected per point during spring calling surveys at Trustom Pond and Ninigret NWRs during the last five years.
  • On July 12, 2008 we participated in the annual butterfly count organized by the National Audubon Society. We surveyed the Ninigret salt pond and headquarters units and volunteers surveyed Trustom Pond fields and along Moonstone Beach Rd and beach. Notable finds include the variegated fritillary at Ninigret and Baltimore checkerspots at Sachuest.
  • During August 2008 we participated in a Regional effort to inventory bee species on National Wildlife Refuges in Region 5. Following the standardized protocols, we placed four transects in open areas at both Trustom and Ninigret for a total of 8 transects. Each transect consisted of 15 total bowls, with five each of three colors. The bowls are left out for 24 hours and then collected and shipped to Patuxent for identification.

Rare plant site management:

  • Hand cutting of shrubs encroaching on the Ninigret Endangered Species area (NESA) is recommended for the winter - spring. This would best be accomplished with a crew of volunteers, but it will be important to have staff present to oversee the operation and also this should occur prior to the growing season to minimize impacts to the rare plants. Alternatively, this site could be mowed during the winter if the ground is frozen.
  • In conjunction with the NEWFS we will be surveying NESA for Platanthera ciliaris and Polygala cruciata var. aquilonia. We will estimate population size, identify potential threats to the site and determine the best way to manage the site long-term.

2008 Management Prescription and Habitat / Resources of Concern Response

Habitat / Invasive Species Management
  • This year (2008) we initiated an Adaptive Resource Management shrub restoration project that focuses on providing high quality habitat for migratory landbirds and New England Cottontail (currently a candidate species). This project involves four refuges (Rachel Carson, Great Meadows, Parker River, and Ninigret). Extensive planning was involved in developing the monitoring protocols for the vegetative community as well as the wildlife of interest. Long term vegetative plots will be established to monitor the composition and structure of the plant community.
  • Volunteers continue to monitor invasive plants encroaching on the old runways. This is primarily focused on Autumn Olive, and is an important aspect of the restoration as native plants are colonizing and gaining the advantage.

Monitoring and Surveys – Resources of Concern
New England Cottontail:
During the winter we will be collecting pellets for DNA testing at UNH as well as to support development of another potential technique being investigated at Patuxent. We hope to have a better idea of the distribution and abundance of this species on Ninigret where they were documented in 2006. Using pellets for DNA analysis (as developed in the northern part of the range) has proved difficult in recent years when snowfall has been minimal, so if we continue to have difficulty collecting samples we will be looking to develop additional techniques for detecting and monitoring this species.

Migrant Landbirds:
On September 1, 2008 we initiated a fall banding station at the Salt Ponds unit of Ninigret NWR to document the diversity and abundance of fall migrating landbirds. A total of 17 net lanes were constructed within a 20 acre portion of the refuge. Approximately 14 acres is dominated by mature shrub and 6 acres is regenerating runway comprised almost exclusively of northern Bayberry. We opened between 5 to13 nets 4-5 days per week through October 31, 2008. The number of open nets depended on the weather and capture rate. We banded a total of 1079 birds of 51 species.

2008 Management Prescription:

Habitat actions:
The seasonal crew hand pulled several patches of J. Stiltgrass in the woods adjacent to the Kettle Pond parcel of Ninigret. Approximately 10 full bags were discarded and we successfully removed all fruit bearing plants. This was the second year of this effort and we noted significantly smaller patches this year. It may take several years to exhaust the seed bank.

Resource monitoring:
Landbird breeding surveys were conducted this year for the second consecutive year on the Headquarter and Lewis Trail tracts. A total of 23 (9 and 14, respectively) points were surveyed twice between May 30 and June 10. We detected 32 species in 2008 with eastern towhee, tufted titmouse, ovenbird, eastern wood-pewee and black-capped chickadee being the most common.

Last updated: January 10, 2012