northern long eared bat habitat assessment · is more open, creating some open flyways and forage...
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Northern Long Eared Bat Habitat Assessment
Project Site: Sampson’s Mill Road, Cotuit MA
Prepared For: Borrego Solar, Inc.
Prepared by: Steven Riberdy, MS, CWB®, PWS, CE
GZA GeoEnvironmental, Inc.
Survey Date: 10/06/16
INTRODUCTION
The purpose of this study was to assess the potential habitat conditions at the above referenced site for
the State and Federally protected Northern Long‐Eared Bat – Myotis septentrionalis (NLEB). The study
site, under consideration by Borrego Solar Systems, Inc. as a potential solar generation facility, may
require tree removal. The parcel is located within the US Fish & Wildlife Service (USFWS) NLEB buffer
zone. Projects within this zone that require a Federal or State permits (e.g., Stormwater Pollution
Prevention Plan, Section 404 permit) must perform a due diligence review for NLEB under Section 7 of
the Federal Endangered Species Act (ESA) following the final 4(d) rule issued in February, 2016. Due
diligence includes determining if any known hibernacula or maternity roost trees have been
documented on or proximal to the property where the proposed work will occur. In addition, under
Section 7(a)(1) of the ESA, the Federal agency initiating the Section 7 review (US ACOE‐404 program,
US EPA‐SWPPP), may reject the generic Biological Opinion (BO) established under the 4(d) rule and
require further investigation of a site, for the purpose of furthering the conservation of this species, if
the agency determines that NLEB, or its habitat, may be impacted. If the NLEB is found to be likely
present, the agency may require additional surveys in the form of acoustic monitoring, mist netting or
radio telemetry. Therefore, at your request, we have conducted the required due diligence review of
the entire parcel per the final 4(d) rule (50 CFR Part 17), as well as performed a full Phase I NLEB site
assessment of the area of proposed impact and areas proximal to the proposed impact at the above
referenced site. The purpose of this additional on‐site due diligence review was to:
further document any potential for NLEB habitat affected by the proposed project, and
describe the relative quality of any NLEB habitats found and describe the potential for NLEB to
occur within the impact area.
Based upon this review, it is GZA’s professional opinion that the potential project site located off of
Sampson’s Mill Road in Cotuit, MA is unlikely to have the potential for NLEB hibernacula or maternity
roosting tree habitat onsite and none are known within ¼ mile of the parcel. Forage potential, or
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general summer habitat, is likely present. The following is a summary of this due diligence review and
on‐site documentation for your records.
DUE DILIGENCE REVIEW
Per the Final 4(d) rule, we performed a due diligence records review of known NLEB overwintering sites
and maternity roost trees on, or proximal to, your project site. This review accessed the US FWS ‐ IPaC
web site to check for records as well as the Massachusetts Natural Heritage and Endangered Species
Program (MA NHESP) database. The IPaC request identified that the site is located in potential NLEB
habitat. Therefore, a full Phase I assessment was conducted to determine the likelihood of the site
providing actual NLEB habitat and, if such habitat was found present, to further assess the quality of
the habitat features and functions relative to NLEB. The MA NHESP database search (conducted on
October 05, 2016, data last updated on May 24, 2016) found none of these habitat features on, or
proximal to, the property where the proposed project will occur. Maternity roost trees were considered
proximal if they were located within 150 feet of the property boundaries as shown on the provided plans.
Winter hibernacula were considered proximal if they were located on site or within ¼ mile of the parcel
boundaries as provided to our office.
PHASE I ONSITE NLEB HABITAT ASSESSMENT
In addition to the required due diligence review, GZA also conducted a full Phase I habitat assessment
of the work area on site to characterize the habitats and assess the potential these habitats provide for
NLEB.
Study Methodology
The NLEB habitat assessment was conducted by Mr. Steven Riberdy, M.S. Senior Ecologist, CWB. The
survey included walking all areas of the proposed cutting as well as areas immediately adjacent areas.
A natural community map of all habitats found was then created based upon field observations. Each
natural community unit was assessed for the potential to support NLEB summer roosting and foraging
habitat. Within each natural community unit, dominant and common vegetation assemblages were
identified by stratum. Within the tree stratum, average dbh, canopy cover, and species composition
were assessed. Particular attention was paid to standing dead trees, high snag density, clutter density,
or other trees that may provide roosting locations. Standing dead trees were assessed relative to their
size, size relative to other trees, location, distribution and degree of decay. Notes on structural diversity
and complexity of each natural community unit as well as other habitat features associated with NLEB
(corridors, water sources, etc.) were made to better inform this qualitative bat habitat assessment. The
cutting area was assigned a value as to whether it provided no, very limited, limited, good or optimal
habitat to the NLEB with respect to both forage and roosting habitat.
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Habitat Assessment
The study area is a 29± acre area located
on the north and south sides of
Sampson’s Mill Road, in Cotuit, MA. The
majority of the site is comprised of
forested upland habitat and part of a
larger, 400 acre, habitat block
maintained by the town as watershed
protection land. The site is bordered by
Mariner Circle to the north, Main Street
to the west and extensive forested areas
to the east and south. Within the site,
short, dense tree canopy covers the
entire are of potential development.
A single natural community type
dominates the site, which for descriptive
purposes has been split into two study
areas.
Site A (Forested Upland), North Side
of Sampson’s Mill Road, (17± ac), and
Site B (Forested Upland), South Side of Sampson’s Mill Road, (12± ac).
Site A: This area is located along the north side of Sampson’s Mill Road and is a roughly 1,500 foot long
by 500 foot wide area comprised of a uniform forested upland community. This area is forested with a
mixture of coniferous and deciduous species with white pine, red oak, white oak, black oak and red
maple comprising 90% of the canopy. There is a good mix of white pine (40%) and deciduous tree
species (60%) which comprise the canopy other common canopy tree species include pitch pine,
sassafras and black birch. Overall, the canopy is short (50‐70’) with the white pine comprising almost all
of the trees >60’ in height. For the most part this forested community young, with most trees (60%)
being 3‐8” dbh, and a smaller percentage (30%) in the 8‐15” dbh class, most of which are white pine.
Very few (>10%) of the canopy trees are greater than 15” dbh, and again are mostly larger white pines.
The understory and sub‐canopy are both very dense, and create a complex and cluttered understory.
Canopy tree regeneration as well as lower branching in the short deciduous tree canopy make up the
sub‐canopy layer while tree regeneration, highbush blueberry, arrowwood, shadbush, mountain laurel
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and maple leaf viburnum make up the shrub layer. The groundcover is moderate to dense with a carpet
of lowbush blueberry, green brier, huckleberry and poison ivy present throughout most of the forested
area. Other common groundcover species includes wintergreen, bracken fern, sheep laurel,
sarsaparilla, hayscented fern, lady slipper and Pennsylvania sedge.
There are no water sources (open water) or wetland areas located within or proximal to the study area.
Some open water is present west of the site in the form of a small kettle pond, which is located >1,000
feet from the study area. There are also limited trails or corridors within the study area for internal
NLEB movement. Standing dead trees are few in number, with <1% of all standing dead tree boles dead.
In total only five standing dead tree boles were found, most in the 8‐12” age class. Two of these had
exfoliating bark that could be used for NLEB roosting, while the other three were devoid of bark and
limbs. Of the live trees, only a low percent (<1%) of these had head limbs or exfoliating bark useful for
NLEB roosting.
Site B: This area is located on the south side of Sampson’s Mill Road, south of a wide powerline
easement that bisects the forested watershed protection parcel. This area is also completely forested
upland habitat and in general very similar in vegetative composition to Site A. The difference here is
that the overall assemblage of trees has less white pine (20%), with the deciduous trees of a similar
composition as Site A. The canopy trees here are smaller (70%; 3‐8” dbh) with a shorter canopy (40‐
60’). The understory and shrub layers are also very dense and cluttered, similar to Site A. The shrub layer
is more open, creating some open flyways and forage areas beneath the sub‐canopy. Groundcover is
near identical to Site A, with a carpet of lowbush blueberry present throughout the upland areas.
Again similar to Site A, this area has no open water or wetlands located within the site. The cluttered
site has few trails or flight corridors within. However, the open sub‐canopy is more conducive to forage
and gleaning habits of the NLEB than Site A. Standing dead trees are fewer in number than Site A,
mainly due to the lack of larger trees and overall young age of the forest. Standing dead tree boles make
up less than 1% of the overall site and only three were found that contain exfoliating bark. These were
all <10” dbh trees. Of the live trees, only a small percentage (<1%) had features conducive to NLEB
roosting.
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Findings
Summer Habitat: For this assessment, we have rated all forested and edges habitat areas as to their
degree of forage and roosting potential for this species. Areas were classified as:
no habitat present;
“limited or very limited” habitat;
“good” habitat; or
“optimal” habitat.
On site, the vast majority of the site (Sites A and B) offer limited habitat value to the NLEB. These
forested areas likely provide some limited to good forage opportunities, also with a very limited
capacity to support roosting sites. If roosting were occurring on site, it is expected to be limited to
solitary roosting males as no sign of maternity roosting colony habitat were found.
Overwintering Habitat: Based upon our site inspection, there is no evidence of the presence of
overwintering habitat. The closest location of documented overwintering for this species is located
several miles away from the site. The local geology is not conducive to the formation of natural caves.
However, this in this part of the state recent studies have shown that hibernacula may be located in
other structures such as buildings, cistern, large culverts or wells. No such structures were found on site
nor were identified in our due‐diligence review.
Phase I NLEB Habitat Assessment and Due Diligence Review Summary: Overall, the proposed work
area does not provide important habitat for the NLEB. The forested portions of the site offer limited
habitat, limited to general forage opportunities found within the forested areas of the site, along with
very limited roosting habitat. The impact to forested habitat will be limited to a 29.0 acre area of the
site which is situated in a larger 400 acre protected habitat block. Therefore, there would appear to be
no limitations to site development relative to the potential presence of NLEB. It is not expected that the
potential presence of NLEB onsite would warrant a more advanced acoustic or mist‐net survey as site
use and NLEB density would be very low. The NLEB Habitat Criteria and potential presence on site are
summarized in the table below.
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NLEB Habitat Criteria Present?
Sites A and B
Known hibernacula within ¼ mile of site No
Known maternity roost trees within 150’ of site No
Potential maternity roost trees on site No
Potential good to optimal forage habitat on site Yes
Potential good to optimal roosting habitat on site No
Potential for NLEB to be found on site for any part of their life cycle Low (forage only)
If you have any questions regarding this Report, please feel free to contact the undersigned at your
convenience at 413‐726‐2100.
Sincerely,
GZA, Inc.
Steven Riberdy, PWS, CWB, PSS Paul G. Davis, PhD, PWS
Senior Ecologist Consultant Reviewer
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Attachments Description of NLEB Habitat Characteristics
Site Habitat Photos
US FWS Phase I NLEB Habitat Assessment Forms
Limitations of Survey
Northern Long Eared Bat Habitat Overview
Northern Long Eared Bat (Myotis septentrionalis) Habitat
The basic summer and winter habitat characteristics of the Northern Long‐Eared Bat are described
below.
Roosting / Foraging Habitat (Summer Habitat): During spring and summer months (April‐August) NLEB’s
are usually found foraging and roosting in deciduous forested habitats. This species typically roosts in
clustered stands of large trees, especially in live or dead hardwoods with tall cavities. However, this
species has been found to roost in other trees, some as small as 3 inch dbh. In addition, human made
structures can sometimes be utilized. Summer roosting / forage habitat, while loosely defined as
“wooded habitats”, does have some particular micro‐habitat features that make a particular forested
area more or less conducive to the NLEB life history needs. Roost trees in forested areas tend to be
clustered in stands of large trees (>16” dbh, having more hardwood than softwood, more total dead
basal area, and larger average live tree diameter than other nearby forested areas (Sasse 1995, Broders
and Forbes, 2004). NLEB’s also tend to use older, intact forest interiors over more managed ones and
also tend to roost in higher elevations on sites (mid and upper slopes) as compared to low elevation
areas, therefore often favoring upland conditions. One important factor in several studies is the size
and type of tree. Trees with naturally exfoliating bark (e.g., shagbark hickory) provide natural roosting
locations (exfoliating bark) whether the tree is alive or dead, while most of the other species that this
species prefers (maple, ash, beech, oak) need to be standing dead to contain appropriate roosting
locations. The degree of decay of a standing dead tree as well as the overall amount of standing dead
and location proximal to one another is another important factor in determining the quality of potential
roosting habitat. Forest stands that are older or have a mixture of age classes often have more standing
deadwood, standing deadwood in various states of decay and potential to generate future standing
dead trees as older ones lose their bark and fall down thereby maintaining the roosting quality of a site.
NLEB’s tend to inhabit dead deciduous trees in mid‐stages of decay, where the tree still has exfoliating
bark but is still structurally sound. Groups of several large stands of dead trees provide ideal roosting
habitat. In general all forested areas contain some percent of standing dead (1‐2%), sites with a greater
percentage, (5%), with the standing dead trees present being clustered and of a size typically larger
than the average dbh of those in the surrounding forested areas are preferred over areas with sparse,
small, standing dead distributed relatively evenly throughout the forested habitats.
Canopy cover is another factor in determining roosting habitat quality, the degree to which is uncertain
and likely varies geographically (Whalen and Krusac, 2014). NLEB’s tend to prefer roost trees with lower
level of solar radiation, as compared to Indiana Bat, especially in areas with a more open canopy within
the surrounding forested habitat.
May 17, 2016 NLEB Overview
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Summer “maternity colonies” tend to be in areas with more ideal roosting conditions such as larger
diameter trees, often in clusters, and a greater percentage of standing dead trees present. Female bats
tend to congregate into these maternity colonies, to raise their pups between May 15 and August 15.
They tend to select larger, dead trees with more open canopies to increase solar radiation, with selected
roost trees located in close proximity to other suitable roost trees. Females tend to periodically switch
roost trees during the summer. (O’Keefe, 2009). Male NLEB’s roost singly and can be found in more
marginal roosting habitats, often in damaged parts of live trees or in areas where dense clusters of good
habitat are not present.
NLEB’s forage within forested habitats, often near roosting sites and within more complex (cluttered)
and structurally diverse habitats, as the forage opportunities are greater in these habitats. NLEB’s
forage below the canopy but above shrub layer mainly gleaning insects off of leaf surfaces. Specific
habitat features that are particularly attractive to NLEB forage are vernal pools, small ponds, forest
edges, streams (protected by canopy closure), forest trails, and nearby clearings. In general, this species
forages within forested and edge habitat areas, often avoiding areas of open canopy. The diversity of
the habitat types within an area increase the prey base and thus the quality of NLEB forage habitat.
Forage and roosting habitat associated with areas that have high quality of one habitat attribute but
low to minimal quality of the other are not as useful to this species compared to an area that can
function in multiple capacities. As bats don’t tend to forage far from their roosting sites, having good
to moderate quality forage habitat nearby is critical in indicating high quality habitat for this species.
In general, the more complex the habitat, with a greater mix of large and small trees, with a relatively
high percentage of standing dead in various states of decay, provides more optimal habitat conditions.
In contrast, monotypic stands or younger trees, and stands with low percentages of standing dead
spread evenly over the area provide less ideal roosting habitats. Quality roosting locations combined
with habitat complexity creates overall ideal summer conditions for the NLEB.
Overwintering Habitat (Winter Habitat): NLEBs overwinter in caves and mines, and sometimes in similar
human structures such as bridges, train tunnels and hydroelectric dams. Within these hibernacula, bats
nest singly or in small groups often with other congeners. They hibernate in cracks and old drill holes
within these habitats. The key factor in overwintering habitat location is its ability to maintain a fairly
constant above freezing temperature and high humidity. The location of suitable overwintering
locations is a limiting factor in the landscape and likely affects the overall distribution of the bats across
the range. NLEB’s do travel from their overwintering location to their summer roosting grounds but
densities of NLEB’s tend to be highest in the forested habitats closer to overwintering sites. Near the
overwintering locations, is also where swarming after spring emergence and before fall return to the
hibernacula occurs; also the time when mating is most likely to occur.
SITE PHOTOS
Samson’s Mill Road, Site A on Left
Site A: Upland Forest
SITE PHOTOS
Site A: Upland Forest
Site A: Upland Forest
SITE PHOTOS
Site A: Typical Standing Dead
SITE PHOTOS
Site B: Upland Forest
Site B: Upland Forest
SITE PHOTOS
Site B: Upland Forest
Powerline north of Site B
SITE PHOTOS
Site B: Typical Snag
APPENDIX A PHASE I SUMMER HABITAT ASSESSMENTS
NOTHERN LONG EARRED BAT (NELB)
HABITAT ASSESSMENT SHEET Project Name: Sampsons Mill Road – Cotuit MA Date: 10/6/2016
Township/Range/Section: Cotuit (Barnstable), MA
Surveyor: S. Riberdy, CWB
Lat/Long/Zone: 70d 26’ 23.136” W / 41d 38’ 4.416” N
Brief Project Description Solar Farm, project located on forested watershed land. * See attached report
Project Area
Project
Total Acres Forest Acres Open Acres
29 ac 29 ac 0
Proposed Tree Removal (ac)
Completely Cleared
Partially Cleared (will leave trees)
Preserve acres –no clearing
29 ac 0 0
Vegetation cover types
Pre‐Project Post Project
100” forested watershed land (upland forest) * See attached report
‐ solar farm
Landscape within 5 mile radius
Flight Corridors to other forested areas?
Yes. Limited, powerline corridor passes through 400 acre forested watershed land, approx. 30 acres of the 400 proposed to be developed
Describe Adjacent Properties (e.g. forested, grassland, commercial or residential development, water sources)
400 acres of forested habitat in forested block. SF residential around forested area.
Proximity to Public Land
What is the distance (mi.) from the project area to forested public lands (e.g. national or state forests, national or state parks, conservation areas, wildlife management areas)?
Site is within 400 acres of public land
APPENDIX A PHASE I SUMMER HABITAT ASSESSMENTS
Use additional sheets to asses discrete habitat types at multiple sites in a project area.
Include a map depicting locations of sample sites if assessing discrete habitats at multiple sites in project area.
A single sheet can be used for multiple sites, if habitat is the same.
Sample Site description
Sample Site No. (s) A: North Site
Upland Forest (Mixed)
Water Resources at Sample Site
Stream Type (# and length)
Ephemeral Intermittent Perennial Describe exiting condition of water sources:
NONE
Pools/Ponds (# and size)
Open and accessible to bats?
Wetlands (approx.)
Permanent Seasonal
Forest Resources at Sample Site
Closure/Density
Canopy (> 50’) Midstory (20‐50’) Understory (< 20 ‘) 1=1‐10%, 2=11‐20%, 3=21‐40%, 4=41‐60%,
5=61‐80%, 6=81‐100%
6 5 4
Dominant Species of Mature Trees
Red Oak, White Pine, White Oak
% of Trees w/ Exfoliating Bark <1% 0 0
Size Composition of Live Trees (%)
Small (3‐8 in) Med (9‐15 in) Large (> 15 in)
60% 30% <10%
No. of Suitable Snags 5
Standing dead trees with exfoliating bark, cracks, crevices, or hollows. Snags without these characteristics are not considered suitable.
IS HABITAT SUITABLE FOR NELB? Yes ‐ Limited
Additional Comments:
High degree of clutter in midstory, young canopy, lack of large trees. Low‐Moderate Forage, Low Roosting, limited flight corridors and no water. See Attached Report
Attach aerial photo of project site with all forested areas labeled and a general description of the habitat.
Photographic Documentation: Habitat shots at edge and interior from multiple locations; understory/midstory/canopy, examples of
potential suitable snags and live trees; water sources.
APPENDIX A PHASE I SUMMER HABITAT ASSESSMENTS
Use additional sheets to asses discrete habitat types at multiple sites in a project area.
Include a map depicting locations of sample sites if assessing discrete habitats at multiple sites in project area.
A single sheet can be used for multiple sites, if habitat is the same.
Sample Site description
Sample Site No. (s) B: South Site
Upland Forest (Mixed)
Water Resources at Sample Site
Stream Type (# and length)
Ephemeral Intermittent Perennial Describe exiting condition of water sources:
NONE
Pools/Ponds (# and size)
Open and accessible to bats?
Wetlands (approx.)
Permanent Seasonal
Forest Resources at Sample Site
Closure/Density
Canopy (> 50’) Midstory (20‐50’) Understory (< 20 ‘) 1=1‐10%, 2=11‐20%, 3=21‐40%, 4=41‐60%,
5=61‐80%, 6=81‐100%
6 5 3
Dominant Species of Mature Trees
Red Oak, White Pine, White Oak
% of Trees w/ Exfoliating Bark <1% 0 0
Size Composition of Live Trees (%)
Small (3‐8 in) Med (9‐15 in) Large (> 15 in)
70% 20% <10%
No. of Suitable Snags 3
Standing dead trees with exfoliating bark, cracks, crevices, or hollows. Snags without these characteristics are not considered suitable.
IS HABITAT SUITABLE FOR NELB? Yes ‐ Limited
Additional Comments:
High degree of clutter in midstory, young canopy, lack of large trees. Low‐Moderate Forage, Low Roosting, limited flight corridors and no water. Fewer large trees than are A. See Attached Report
Attach aerial photo of project site with all forested areas labeled and a general description of the habitat.
Photographic Documentation: Habitat shots at edge and interior from multiple locations; understory/midstory/canopy, examples of
potential suitable snags and live trees; water sources.
Natural Resource Survey Limitations
1. GZA’s natural resource survey was performed in accordance with generally accepted practices of other consultants undertaking similar studies at the same time and in the same geographical area, and GZA observed the degree of care and skill generally exercised by other consultants under similar circumstances and conditions. GZA’s findings and conclusions must be considered not as scientific certainties, but rather as our professional opinion concerning the significance of the limited data gathered during the course of the survey. No other warranty, expressed or implied, is made.
2. The conclusions presented in the report were based solely upon the services described therein, and not on scientific tasks or procedures beyond the scope of described services or the time and budgetary constraints imposed by Client. The work described in this report was carried out in accordance with the terms and conditions of our contract for this project.
3. The purpose of this study was to assess the biological site conditions, subject to the terms and limitations of the contractual agreement as well as seasonally imposed conditions affecting the conditions and biological diversity present at the time of observation.
4. The observations described in this report were made on the dates referenced and under the conditions stated therein. Conditions observed and reported by GZA reflect the actual conditions that could be reasonably observed based upon the visual inspections of surface conditions at the specific time of observation. Such conditions are subject to environmental and circumstantial alteration beyond the control of GZA and may not reflect conditions observable at another time.
5. The conclusions and recommendations contained in this report are based upon the data obtained from a limited number of surveys performed on the site as described in the report. There may be variations between these surveys and other past or future surveys due to inherent environmental variability.