HomeMy WebLinkAboutTHORELL PARK SUBDIVISION (FORMERLY JOHNSTON ANNEXATION) - PDP - PDP160032 - SUBMITTAL DOCUMENTS - ROUND 1 - ENVIRONMENTAL REPORTECOLOGICAL CHARACTERIZATION STUDY:
JOHNSTON ANNEX
June 2016
Prepared by:
www.habitatmanagementinc.com
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Table of Contents
1 Introduction ............................................................................................................................. 1
2 Site Description ....................................................................................................................... 1
3 Ecological Characterization ..................................................................................................... 1
3.1 Wildlife............................................................................................................................. 2
3.2 Wetlands ........................................................................................................................... 2
3.3 Prominent Views .............................................................................................................. 6
3.4 Native Trees and Vegetation ............................................................................................ 7
3.5 Non-Native Trees and Vegetation .................................................................................... 8
3.6 Bank, Shoreline, and High Water Mark of Perennial Water ............................................ 9
3.7 Sensitive and Specially Valued Species ........................................................................... 9
3.8 Special Habitat Features ................................................................................................. 13
3.9 Wildlife Migration Corridors ......................................................................................... 13
3.10 General Ecological Functions ..................................................................................... 13
3.11 Timing of Development in Relation to Ecological Character .................................... 13
3.12 Mitigation Measures ................................................................................................... 13
Figure 1. Pond with wetland fringe, island, and willow grove. ...................................................... 6
Figure 2. View from near pond, looking north, with introduced pasture in foreground. ............... 7
Figure 3. View from eastern edge of property looking west. ......................................................... 7
Figures 4, 5, and 6. Trees and shrubs surrounding residence ......................................................... 8
Table 1. Threatened, Endangered, and Candidate Species ........................................................... 10
Appendix 1 - Sensitive and Specially Valued Species ................................................................ A1
ECS: Johnston Annex
Habitat Management Inc. 1 June 2016
1 Introduction
Habitat Management, Inc. has conducted an Ecological Characterization Study (ECS) of the
Johnston Annex property. The owner and engineer intend to develop the property for 170 single-
family attached homes. Article 3, Section 3.4.1 of the City of Fort Collins Land Use Code
requires an ECS if any portion of the development site is within five hundred feet of a ³natural
habitat or feature´OLVWHGLQWKHFRGH The feature of interest on the site is a small man-made pond
and associated wetland fringe. The current development plan does not provide for preservation of
the pond.
2 Site Description
The Johnston Annex property is located at approximately 40.501078 N, 105.046804 W (Map 1).
The property is zoned as low-density mixed use residential (LMN). The property is comprised of
a flood-irrigated pasture surrounding a small man-made pond, a single family residence which
includes a sod grass yard and associated landscaping, and some corrals and barns. A residential
neighborhood is located immediately to the south. A new housing complex is under construction
immediately to the east. Similar irrigated pastures/hay fields are located to the north.
Immediately to the west, are the Union Pacific railroad tracks and a walking path with residential
development further to the west.
The property is grazed by a small herd of cattle (Dexter cows), the homeowner maintains various
farm animals in corrals behind the house including horses and goats; domestic dogs and cats are
also present on the property. The pond is fed entirely by irrigation water and dries out if not
regularly filled by the landowner.
3 Methods
A data review was conducted to gather information and assist in the evaluation of potential
natural biological resources within the property. The data review entailed an evaluation of online
resources and publications to determine the presence or potential occurrence of important natural
and biological resources. This data review included:
x US Fish and Wildlife Service (USFWS) Federally Listed and Proposed Endangered,
Threatened, and Candidate Species and Critical Habitat in Larimer County as identified
by the USFWS Information, Planning, and Conservation System (IPaC) Official Species
List and Critical Habitat Mapper;
x Migratory Bird Treaty Act (MBTA) and Bald and Golden Eagle Protection Act (BGEPA)
protected species as identified on the IPAC Trust Resources Report;
x The Colorado Natural Heritage Program database statewide species and natural
community tracking list for Larimer County, Colorado;
x Colorado Parks and Wildlife Threatened and Endangered Species List;
x Colorado Parks and Wildlife Online Hunting Atlas;
x Species identified as in need of protection in the City of Fort Collins Natural Areas
Policy Plan;
x The City of Fort Collins Land Use Code;
ECS: Johnston Annex
Habitat Management Inc. 2 June 2016
x The City of Fort Collins Natural Habitat and Features Inventory GIS Data - taken from
April 1999 aerial photography;
x USFWS National Wetlands Inventory (NWI) Wetlands Mapper;
x 2015 NAIP aerial photography; and
x FEMA floodplain and hydrologic maps.
Field surveys were conducted by biologists from Habitat Management, Inc. on May 5 and June
9-10, 2016 to evaluate site conditions, determine presence of significant plant communities,
determine presence of significant wildlife species or habitats, and delineate wetlands. Wetland
delineations were conducted using Army Corps of Engineers methods and the Great Plains
regional supplement.
4 Ecological Characterization
4.1 Wildlife
The property provides suitable habitat for a variety of wildlife species adapted to irrigated
introduced pasture in an urban environment. Because the plant species diversity is low the
wildlife diversity is similarly low. Wildlife with the potential to use the property as well as
species observed and species habitat on the property are summarized below.
4.1.1 Big Game
Three big game animals could potentially frequent the property and adjacent area year round:
pronghorn antelope (Antilocapra americana), white tailed deer (Odocoileus virginianus) and
mule deer (Odocoileus hemionus). The value of the property to big game is low due to urban
location of the property. As residential development (urban sprawl) continues in adjoining areas
the value to big game will continue to decline. No crucial big game habitat or migration corridors
are recognized in the property. No big game animals or sign were observed on the property
during the field reconnaissance.
4.1.2 Predators
Mid-sized predators including red fox (Vulpes vulpes) and coyote (Canis latrans) would be
expected to occasionally frequent the property. Mink (Neovison vison), long-tailed weasel
(Mustela frenata), and badger (Taxidea taxus) would be less common visitors. The value of the
property to predators is low due to urban location of the property. As residential development
(urban sprawl) continues in adjoining areas the value to predators will continue to decline. No
predatory animals or sign were observed on the property during the field reconnaissance.
4.1.3 Other Mammals
A variety of small and medium-sized mammal species are known to occur adjacent to the
property, although few were observed on the field reconnaissance. These species include raccoon
(Procyon lotor) and striped skunk (Mephitis mephitis) which thrive throughout urban areas.
Various small rodents including mice, voles, rats, gophers, ground squirrels, and chipmunks are
expected to utilize the property year round. Lagomorphs (jackrabbits ± Lepus spp. and cottontails
± Sylvilagus spp.) would be found on the property. All these prey species are cyclically common,
widespread throughout the region, and are important food sources for raptors and other
predators. Muskrat (Ondatra zibethicus) were observed in the pond, beaver (Castor canadensis)
ECS: Johnston Annex
Habitat Management Inc. 3 June 2016
would be uncommon, but could potentially wander onto the property. Other species such as
porcupines (Erethizon dorsatum) and various bats could also frequent the area. Two common bat
species that are consistently found in Fort Collins and roost primarily in trees are hoary bats
(Lasiurus cinereus) and silver-haired bats (Lasionycteris noctivagans). The value of the property
to mammals is low due to urban location of the property and the land use of grazing, mowing,
and baling the pasture. Cottontails and muskrat were the only two mammals observed on the
property during the field reconnaissance.
4.1.4 Raptors
Raptor species known to occur in the region include turkey vulture (Cathartes aura), bald eagle
(Haliaeetus leucocephalus), ferruginous hawk (Buteo regalis), 6ZDLQVRQ¶VKDZNV Buteo
swainsoni), northern harrier (Circus cyaneus), American kestrel (Falco sparverius), red-tailed
hawk (Buteo jamaicensis), rough-legged hawk (Buteo lagopus), golden eagle (Aquila chrysateos)
and prairie falcon (Falco mexicanus). These species are year-round residents, seasonal visitors,
or migrants, depending on the species. Owl species which could potentially frequent the property
include the barn owl (Tyto alba), great horned owl (Bubo virginianus), long-eared owl (Asio
otus), and the short-eared owl (Asio flammeus). Raptor species such as the northern goshawk
(Accipiter gentilis), screech owl (Megascops spp.), and peregrine falcon (Falco peregrinus) do
not have suitable habitat on or adjacent to the property as they require dense coniferous forests
and riverine cliffs. No habitat is present for burrowing owls (Athene cunicularia) which nest in
prairie dog holes or badger burrows. Nesting habitat in the property is present, but limited, for
tree nesting species. No raptor nests were observed on the property during the field
reconnaissance. There is no suitable bald eagle winter roost habitat in the property. A northern
harrier and a 6ZDLQVRQ¶VKDZN were observed during the field reconnaissance.
4.1.5 Upland Game Birds
Four upland game bird species may occur in suitable habitats within and adjacent to the property.
These species are the mourning dove (Zenaida macroura), wild turkey (Meleagris gallopavo),
gray (or Hungarian) partridge (Perdix perdix), and ring-necked pheasant (Phasianellus
colchicus). No upland game birds were observed on or adjacent to the property during the field
reconnaissance.
4.1.6 Waterfowl and Shorebirds
Various common urbanized waterfowl, shorebirds and other water obligate avian species are
expected to occur as residents to the pond located on the property and other waterbodies in the
region. However, the value of the pond to serve as both resident habitat and migratory stopover
habitat is very limited due to its small size. This pond is typically reduced to a small, isolated
pool and can dry out completely during late summer if not filled. A number of water dependent,
urbanized, avian species could occasionally utilize this habitat including mallards (Anas
platyrhynchos), American wigeon (Anas americana), great blue heron (Ardea herodias), Canada
goose (Branta canadensis), gulls, belted kingfisher (Megaceryle alcyon), swifts, and swallows.
The open water and the wetland vegetation of the pond are suitable habitat for migratory
waterfowl, particularly dabbling foragers. Waterfowl likely use the area for foraging and loafing
and may use the un-mowed tall grass immediately surrounding the pond and on the island for
ECS: Johnston Annex
Habitat Management Inc. 4 June 2016
nesting, though the small size of the area and proximity to development and existing land
management greatly reduces the quality of nesting habitat. This property is not a concentration
area for migratory or nesting waterfowl or shorebirds. The pond is too small and likely freezes
over during wintertime, making it less attractive for concentrations of waterfowl or shorebirds.
Mallards, Canada geese, great blue heron, and American wigeon were observed during the field
survey in and around the pond.
4.1.7 Other Birds
A variety of birds are expected to occur with regularity around the property and occupy the
shrubs, trees, and grasses near the pond. Seasonal and/or year-round use can be expected by a
number of urban adapted birds including American robin (Turdus migratorius), common flicker
(Colaptes auratus), sparrows, magpies (Pica pica), swifts and swallows, crows (Corvus
brachyrhynchos), ravens (Corvus corax), dark-eyed junco (Junco hyemalis), house finch
(Haemorhous mexicanus), western kingbird (Tyrannus verticalis), eastern kingbird (Tyrannus
tyrannus), pigeon (Columbalivia domestica), grackle (Quiscalus quiscula), Eurasian collared
doves (Streptopelia decaocto), jays (Cyanocitta spp.), western meadowlark (Sturnella neglecta),
red-winged blackbirds (Agelaius phoeniceus), yellow headed blackbirds (Xanthocephalus
xanthocephalus), and various woodpeckers. Some ground-nesting species may nest in the tall
grasses immediately surrounding the pond; however, the pasture is routinely mowed, and
managed such that many solitary or sensitive ground nesting avian species would be precluded
from nesting. Killdeer (Charadrius vociferus) were observed nesting along the gravel drive
entering the property. Other birds observed during the during the field reconnaissance included
meadowlark, western kingbird, eastern kingbird, raven, house sparrow, dark-eyed junco, robin,
swallow, grackle, house finch, red-winged blackbirds, and magpie.
4.1.8 Amphibians, Reptiles, and Aquatic Species
Wildlife surveys completed throughout the region have documented various amphibians, reptiles,
and aquatic species. Many of these species are locally common inhabitants within suitable
habitat. However, others are uncommon to rare.
Fish and Aquatic Macro-Invertebrate Species. Aquatic habitat in the property is limited by the
ephemeral nature of the surface water. The lack of deep water habitat and extensive and
persistent water sources limits the presence and diversity of fish and other aquatic species. The
ZDWHUTXDOLW\LQWKHSRQGZRXOGEHUDWHGDV³H[WUHPHO\SRRU´ with very high phosphorous,
ammonia, and salinity levels, and very low dissolved oxygen. The pond becomes eutrophic,
which when extreme can create unpleasant odors associated with methane, hydrogen sulfide, and
ammonia. The input of nutrients into the system from flood irrigation is a dominant factor in the
water quality of this pond. A few fish were observed in the pond during the field reconnaissance.
The landowner reported that the pond may have previously been stocked with bass.
Amphibians and Riparian Reptiles. Locally common riparian species, within suitable habitat in
the region, include western chorus frogs (Pseudacris triseriata), bullfrogs (Lithobates
catesbeianus), plains spadefoot (Spea bombifrons
ECS: Johnston Annex
Habitat Management Inc. 5 June 2016
(terrestrial) gartersnake (Thamnophis elegans vagrans), western painted turtle (Chrysemys picta
bellii), and eastern snapping turtle (Chelydra serpentina serpentine), and ornate box turtle
(Terrapene ornata ornata). The only riparian amphibian or reptile observed on the property
during the field reconnaissance were bullfrogs. Amphibian diversity is known to be limited by
the presence of bullfrogs, a species that was introduced to this area by human activity and is a
known vector for chytrid fungus that can greatly impact amphibian populations. Bullfrogs are
non-native predators eating a wide variety of plants and animals. They have a predatory impact
on native amphibians and potentially on some bird species.
Upland Reptile Species. Common upland reptile species expected on the property would include
the bull snake (Pituophis melanoleucas). Less common upland species may include the prairie
rattlesnake (Crotalus viridis), eastern yellow-bellied racer (Coluber constrictor flaviventris), and
plains hog-nosed snake (Heterodon nasicus). The only upland reptile species observed on the
property during the field reconnaissance was a bull snake.
4.2 Wetlands
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center (Figure 1, Map 1). Continued filling of the pond on an annual basis has contributed to the
development of wetland vegetation and soils in these areas. The wetland hydrology is provided
by irrigation and pond filling.
Two general wetland types were identified at the pond; wet meadow and emergent marsh. The
emergent marsh occurs in the shallow water at the edge of the pond and immediately adjacent to
it. This community is typically four meters or less in width, with a few areas reaching seven
meters in width at the pond corners. The emergent marsh is comprised primarily of cattail (Typha
latifolia), with occasional sedges and rushes (Carex sp., Eleocharis spp., Juncus sp.,
Schoenoplectus sp., and Scirpus sp.). The wet meadow is typically less than 5 meters in width
and is comprised primarily of spikerush (Eleocharis spp.) with some timothy (Phleum pratense)
and occasional cattail. The wetlands covered approximately 0.2 acres. The National Wetlands
Inventory has classified the pond as PABFx - Palustrine Aquatic Bed Semi-permanently
Flooded, Excavated. Examination of available hydrologic and flood data suggests that the pond
is an isolated water and would not be considered jurisdictional by the Army Corps of Engineers.
A request for a Jurisdictional Determination (JD) has been submitted to the Corps.
Typical ecological functions provided by wetlands such as dissipation of energy from storm
flows, filtration of sediments and pollutants, and streambank stabilization do not occur on this
site as it is an isolated water fed by irrigation. The primary ecological function of the pond and
wetland on the property is provision of habitat to the species discussed in Section 4.1. As
discussed in Section 4.1, the value of this habitat is limited due to the small size and width of the
wetland, agricultural use of the surrounding property, urban encroachment, and the fact that the
pond is used for grazing and watering of livestock.
ECS: Johnston Annex
Habitat Management Inc. 6 June 2016
Figure 1. Pond with wetland fringe, island, and willow grove
4.3 Prominent Views
Views across the site to the south and east are met with dense residential development. Looking
across the site to the north is generally obscured by trees but the pond and open pasture would be
visible. The property slopes up on the north edge, generally limiting views much beyond the
property boundary, although additional pastures and trees can be seen (Figure 2). The prominent
view across the site is to the west where the mountains can be seen as well as the residential area
west of the railroad tracks (Figure 3).
ECS: Johnston Annex
Habitat Management Inc. 7 June 2016
Figure 2. View from near pond, looking north, with introduced pasture in foreground
Figure 3. View from eastern edge of property looking west
4.4 Native Trees and Vegetation
Beyond the berm on the western side of the pond, a small grove of peach leaf willow (Salix
amygdaloides) occurs, made up of approximately 27 trees covering approximately 0.4 acres.
American currant (Ribes americanum) and wild rose (Rosa woodsii, Rosa sp.) also occur in this
area. Two plains cottonwood (Populus deltoides) trees occur to the north of the pond along a
small swale. Several small peach leaf willow and coyote willow (Salix exigua) occur on the
island.
ECS: Johnston Annex
Habitat Management Inc. 8 June 2016
Other native vegetation occurring on the site includes occasional western wheatgrass
(Pascopyrum smithii) and a few milkweed (Asclepias sp.). With the exception of the wetland
area and native trees and shrubs, the property is dominated by introduced species.
4.5 Non-Native Trees and Vegetation
Two weeping willow (Salix babylonica) trees occur on the southeast side of the pond. Three
groves of Russian olive (Elaeagnus angustifolia) occur on the south and west sides of the
property made up of approximately 90 trees covering approximately 0.6 acres. Two large
Russian olive trees also occur near the barn. A small grove of approximately 15 aspen trees
(Populus tremuloides) occurs between the driveway and the northern edge of the property. While
this species in native to Colorado it does not naturally occur at low elevations. There is also a
large hackberry (Celtis occidentalis) near the barn and several evergreen and landscape trees
surrounding the house including plum (Prunus sp.), blue spruce (Picea pungens), and elm
(Ulmus sp., Figures 2-4).
The majority of the property is dominated by introduced pasture grasses, especially smooth
brome (Bromus inermis), timothy, and orchardgrass (Dactylis glomerata). Kentucky bluegrass
(Poa pratensis) is also common, as well as the invasive species Canada thistle (Cirsium arvense).
Other introduced species present include bindweed (Convulvulus arvense), dandelion
(Taraxacum officionale), yellow sweetclover (Melilotus officinalis), curly dock (Rumex crispus),
and cheatgrass (Bromus tectorum).
Figures 4, 5, and 6. Trees and shrubs surrounding residence
ECS: Johnston Annex
Habitat Management Inc. 9 June 2016
4.6 Bank, Shoreline, and High Water Mark of Perennial Water
The pond occupies approximately 0.5 acres excluding the island and wetland area. The layout of
the pond and associated wetlands are indicated on Map 1. Pond level may fluctuate depending on
how much water is provided. The pond and nearby grove of peachleaf willow are fenced.
4.7 Sensitive and Specially Valued Species
A current list of Federal threatened, endangered, proposed, and candidate species, and designated
critical habitat that may occur within the boundary of this proposed action and/or may be
affected by this proposed action was obtained from the USFWS Information, Planning, and
Conservation (IPaC) system website. Table 1 lists the endangered, threatened, proposed, and
candidate species and their designated and proposed critical habitat that may occur or could
potentially be affected by activities on the property. Species are discussed in greater detail in
Appendix 1. No USFWS designated critical habitat occurs in or near the property.
ECS: Johnston Annex
Habitat Management Inc. 10 June 2016
Table 1. Threatened, Endangered, and Candidate Species
Species Federal Status Habitat
Habitat
Present?
Determination
Platte River Species
Least tern
Sterna antillarum
Endangered
Sparsely vegetated sandbars on large rivers and
sand/gravel pits.
No water
depletion
No Effect
Pallid sturgeon
Scaphirhynchus
albus
Endangered
Large, free-flowing, warm-water, and turbid
rivers with a diverse assemblage of physical
habitats
No water
depletion
No Effect
Piping plover
Charadrius melodus
Threatened
Sandy beaches, sandflats, dredge islands, and
drained river floodplains.
No water
depletion
No Effect
Western prairie
fringed orchid
Platanthera
praeclara
Threatened
Tall grass prairie on unplowed, calcareous
prairies, and sedge meadows. Upstream
depletions to the Platte River system in
Wyoming may affect the species in Nebraska.
No water
depletion
No Effect
Whooping crane
Grus americana
Endangered
Wetlands, inland marshes, lakes, ponds, wet
meadows and rivers, and agricultural fields.
No water
depletion
No Effect
Mammals
Preble's meadow
jumping mouse
Zapus hudsonius
ssp. preblei
Threatened
ECS: Johnston Annex
Habitat Management Inc. 11 June 2016
Species Federal Status Habitat
Habitat
Present?
Determination
North American
Wolverine
Gulo gulo luscus
Proposed Threatened
Deep, persistent, and reliable spring snow cover
(April 15 to May 14).
No No Effect
Birds
Mexican Spotted
Owl
Strix occidentalis
lucida
Threatened
Nesting/roosting habitat typically occurs either in
well-structured forests with high canopy cover,
large trees, and other late seral characteristics, or
in steep and narrow rocky canyons formed by
parallel cliffs with numerous caves and/or ledges
within specific geologic formations.
No No Effect
Fish
Greenback
Cutthroat Trout
Oncorhynchus
clarki stomias
Threatened
This species inhabits cold water streams and cold
water lakes with adequate stream spawning
habitat present during spring.
No No Effect
Flowering Plants
Ute ladies'-tresses
Spiranthes
diluvialis
Threatened
Seasonally moist soils and wet meadows of
drainages below 7,000 ft. elevation.
Potentially
suitable
No Effect
ECS: Johnston Annex
Habitat Management Inc. 12 June 2016
Species Federal Status Habitat
Habitat
Present?
Determination
Colorado Butterfly
Plant
Gaura neomexicana
var. coloradensis
Threatened
An early successional plant (although probably
not a pioneer) adapted to use stream channel sites
that are periodically disturbed. It occurs on
subirrigated, alluvial (stream deposited) soils on
level or slightly sloping floodplains and drainage
bottoms
Potentially
suitable
No Effect
North Park
Phacelia
Phacelia formosula
Endangered
The species is limited to eroded soil outcrops
composed of barren exposures of the Coalmont
Formation, a coal-bearing substrate in North Park
Colorado.
No No Effect
Insects
Arapahoe Snowfly
Arsapnia arapahoe
Candidate
Stoneflies are primarily associated with clean,
cool, running waters.
No No Effect
ECS: Johnston Annex
Habitat Management Inc. 13 June 2016
4.8 Natural Communities, Habitats, and Special Features
The only habitats identified in the City Land Use Code that occur on the property are the pond,
wetland surrounding the pond, and possibly riparian forest as shown on Map 1 and described in
Sections 4.2, 4.4, and 4.6.
4.9 Wildlife Migration Corridors
The property is located in mostly developed areas of Fort Collins and surrounded by commercial
and residential development. It is highly unlikely that the property serves as a migration corridor
for sensitive, unique, or regionally protected wildlife. The area may provide minimal migratory
benefit to resident urban-adapted wildlife such as red foxes, raccoons, and skunks and it may
provide temporary stopover habitat for migrating birds. Resulting changes to wildlife corridor
quality should be minimal because the property is located in a residential area where wildlife are
already accustomed to structures, roads, bridges, fences, buildings and other habitat
modifications. A review of the Colorado Hunting Atlas indicated no big game migration
corridors.
4.10 General Ecological Functions
The general ecological functions provided by the site have been reduced by multiple human-
induced stressors including suburban development, livestock grazing and haying, agricultural
runoff, presence of aggressive introduced species, and abnormal water regimes. While the pond
provides some benefit to smaller wildlife, electric fencing prevents use by larger species. The
presence of bullfrogs and poor water quality limit the diversity of aquatic species on the site. The
limited scope of the wetland provides minimal habitat for wetland oriented species. The absence
of hydrologic connectivity (outflow) contributes to eutrophication. The native and introduced
trees provide shading, cover, and nesting opportunity for a variety of species; however, the only
nest observed on the site was magpie.
4.11 Timing of Development in Relation to Ecological Character
The Migratory Bird Treaty Act (MBTA) specifically protects migratory birds and their nests
from possession, sale, purchase, barter, transport, import, and export, and take. The regulatory
definition of take (50 CFR 10.12), means to pursue, hunt, shoot, wound, kill, trap, capture, or
collect, or attempt these actions.
It is recommended that removal of the pond and trees be conducted from late summer to late
winter to avoid the avian nesting and breeding season. If this timing is not compatible with
construction schedules, an additional survey should be implemented prior to commencement of
construction to ensure MBTA compliance. At the time of the site survey the only next observed
was a magpie nest.
4.12 Mitigation Measures
Mitigation for removal of native and introduced trees can occur with the use of street/parkway
trees currently incorporated into the conceptual plan, as well as inclusion of shade trees in the
planned open space on the southwest corner of the property. Project designers will select tree
species appropriate to the area that will provide ecological, shade, canopy, aesthetic, and cooling
ECS: Johnston Annex
Habitat Management Inc. 14 June 2016
value, and coordinate if necessary with the City Forester. Project design will comply with the
&LW\¶V/DQG8VH&RGH Section 3.2.1 ± Landscaping and Tree Protection.
Proposed options available to mitigate for the removal of the pond and wetlands include cash in
lieu, enhancement of storm water detention structures, and enhancement of a nearby pond and
wetlands. The preferred alternative is a payment in lieu of onsite mitigation that could be
directed to the conservation of high-quality aquatic habitat elsewhere in the region.
Options for onsite mitigation include the utilization of two planned storm water detention
structures that will collect runoff from the site. These structures will occupy approximately 0.6
acres. While still currently in the design phase, elements could be incorporated to include the
potential establishment of native wetland and upland vegetation in these structures. Native
wetland and upland seed mixtures could be used in the final landscape plan to provide the
opportunity for native plant community and wetland establishment. While the detention
structures will typically dry between storm events, species that can tolerate both wet and drier
conditions could be incorporated into the design. This vegetation may facilitate pollutant and
sediment removal from the storm water flows before it is returned to the drainage system. At this
time, it is unknown if storm water flows would provide adequate hydrology to support long term
wetland development. At a minimum, establishing native upland vegetation in the detention
structures would provide additional habitat opportunities and minimize the need for irrigation
and maintenance of these areas.
An additional mitigation opportunity exists adjacent to the Johnston Annex property to the north.
This adjacent property contains a three-acre pond that, while also man-made, is not dependent on
regular filling. Pond and/or wetland enhancement activities could be implemented to enhance the
wetland and aquatic habitat, given approval by the property owner. Potential opportunities
include the following.
x Supplemental irrigation water (if available) to create variability in the hydrologic regime
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availability of water for such an effort would be required.
x Supplemental seeding or planting of herbaceous wetland vegetation.
x Supplemental planting of wetland or riparian trees and/or shrubs to provide additional
habitat and shading.
x Efforts to ensure preservation of this larger pond in the long-term through conservation
efforts and waWHUPDQDJHPHQW$QLQYHVWLJDWLRQLQWRWKHSRQG¶VK\GURORJ\DQG
availability of water for such an effort would be required.
ECS: Johnston Annex
Habitat Management Inc. 15 June 2016
5 References
City of Fort Collins 2005. Fossil Creek Natural Areas Management Plan. Community Planning
and Environmental Services, Natural Resources Department, Natural Areas Program.
City of Fort Collins. Natural Habitat and Features Inventory GIS Data - taken from April 1999
aerial photography (http://www.fcgov.com/gis/downloadable-data.php).
City of Fort Collins 2003. Resource Management & Implementation Plan for Fossil Creek
Reservoir Regional Open Space. Community Planning and Environmental Services, Natural
Resources Department, Natural Areas Program.
Colorado Parks and Wildlife Online Hunting Atlas
(http://ndismaps.nrel.colostate.edu/index.html?app=HuntingAtlas).
Colorado Parks and Wildlife Threatened and Endangered List
(http://cpw.state.co.us/learn/Pages/SOC-ThreatenedEndangeredList.aspx).
FEMA National Flood Hazard Layer (Official)
(http://fema.maps.arcgis.com/home/webmap/viewer.html?webmap=cbe088e7c8704464aa0fc34e
b99e7f30).
USFWS Information, Planning, and Conservation System (IPaC) Official Species List and
Critical Habitat Mapper (https://ecos.fws.gov/ipac/).
USFWS National Wetlands Inventory (NWI) Wetlands Mapper
(https://www.fws.gov/wetlands/Data/Mapper.html).
USFWS Platte River Recovery Implementation Program (http://www.fws.gov/platteriver).
All online data accessed June 2016.
Appendix 1
Habitat Management Inc. A1 June 2016
Appendix 1 - Sensitive and Specially Valued Species
Platte River Species and Critical Habitat. Three bird species (least tern, piping plover, and
whooping crane), one fish (pallid sturgeon), and one plant (western prairie fringed orchid) are
collectively referred to DV³3ODWWH5LYHU6SHFLHV´7KHSURSHUW\LVORFDWHGZLWKLQWKH3ODWWH River
watershed. The Platte River Recovery Implementation Program details requirements and
procedures for minimizing impacts from water-related activities in contributing watersheds. If a
proposed action may lead to consumptive use of water or have the potential to affect water
quality in the Platte River System, there may be impacts to threatened and endangered species
inhabiting the downstream reaches of this river system.
Subdivision development DFWLYLWLHVDUHQRW³ZDWHU-UHODWHGDFWLYLWLHV´ RU³ZDWHU-depleting
DFWLYLWLHV´WKDWKDYHDQ\SRWHQWLDOWREHDFRQWULEXWLQJIDFWRULQMHRSDUGL]LQJWKHH[LVWHQFHRI
these Platte River Species or adversely affecting designated critical habitat. These Platte River
Species have never been documented at or around the property. It is anticipated that this
proposed project will have no effect on Platte River Species or Platte River Species critical
habitat.
Preble's Meadow Jumping Mouse. 7KH3UHEOH¶Vmeadow jumping mouse 3UHEOH¶V
Appendix 1
Habitat Management Inc. A2 June 2016
Mexican Spotted Owls. Mexican spotted owls nest and roost in well-structured forests with high
canopy cover, large trees, and other late seral characteristics, or in steep and narrow rocky
canyons formed by parallel cliffs with numerous caves and/or ledges within specific geologic
formations. Suitable habitat for spotted owls is not present on the property and development of
this project will have no effect on Mexican spotted owls.
Greenback Cutthroat Trout. Greenback cutthroat trout inhabit cold water streams and cold
water lakes with adequate stream spawning habitat present during spring. Suitable habitat for
trout is not present on the property and development of this project will have no effect on
greenback cutthroat trout.
8WH/DGLHV¶-Tresses. VHJHWDWLRQDQGK\GURORJ\W\SHVRFFXSLHGE\8WHODGLHV¶-tresses include
moist meadows associated with perennial stream terraces, floodplains, oxbows, seasonally
flooded river terraces, subirrigated or spring-fed abandoned stream channels and valleys, and
lakeshores. Human-made features such as irrigation canals, berms, levees, gravel pits, and
reservoirs are also occupied. Surrounding vegetation is not dense or heavily grazed and periodic
or recent disturbance maintains a minimal amount of competition. Ute laGLHV¶-tresses occur
primarily in areas where vegetation is relatively open and not overly dense, overgrown, or
heavily over-grazed. Vegetative cover tends to range from 75% to 90% and is usually less than
45 centimeters tall. The orchid seems intolerant of shade and is usually found as small scattered
groups that occupy relatively small areas of open vegetation within the riparian system.
The closest known occurrences of 8WHODGLHV¶-tresses are near the northwest boundary of Fort
Collins on Overland Trail, south of Michaud Lane. Field reconnaissance of the property
indicated WKDWWKHSURSHUW\LVQRWVXLWDEOHKDELWDWIRU8WHODGLHV¶-tresses for the following reasons.
x Vegetation along the pond is dominated by introduced species that are not associated
with Ute ODGLHV¶-tresses.
x Soils in the property are clay and clay loam soils, rather than the sand and gravel deposits
LQKDELWHGE\8WHODGLHV¶-tresses.
x The pond is not associated with a perennial tributary to the South Platte River.
No 8WHODGLHV¶-tresses were observed on the property and it is anticipated that development of
this project will have no effect on 8WHODGLHV¶-tresses.
Colorado Butterfly Plant. The Colorado butterfly plant is an early successional plant adapted to
stream channels that are periodically disturbed. It occurs on subirrigated, alluvial soils on level or
slightly sloping floodplains and drainage bottoms at 5,000±6,400 feet. Colonies are often found
in low depressions or along bends in wide, active, meandering stream channels a short distance
upslope of the actual channel. The plant requires early-to mid-succession riparian habitat.
The closest known occurrences of Colorado butterfly plant are within the City-managed
Soapstone Prairie Natural Area near the Wyoming border. The USFWS has not established
formal survey guidelines for Colorado butterfly plant, but has indicated that areas similar to, and
slightly drier than, 8WHODGLHV¶-tresses habitat should be assessed. Field reconnaissance of the
Appendix 1
Habitat Management Inc. A3 June 2016
property indicated that it is not suitable habitat for Colorado butterfly plant for the following
reasons.
x Vegetation along the pond is dominated by introduced species that are not associated
with Colorado butterfly plant.
x Soils in the property are clay and clay loam soils, rather than the sand and gravel deposits
inhabited by Colorado butterfly plant.
x The pond is not associated with a perennial tributary to the South Platte River.
No Colorado butterfly plants were observed on the property and it is anticipated that
development of this project will have no effect on the species.
North Park Phacelia. North Park phacelia is found only in North Park (Jackson County, CO). It
occurs on the sides of sandy bluffs at elevations of about 7,940 to 8,260 feet. The species is
limited to eroded soil outcrops composed of barren exposures of the Coalmont Formation, a
coal-bearing substrate. Suitable habitat for North Park phacelia is not present on the property and
development of this project will have no effect the species.
Arapahoe Snowfly. Arapahoe snowfly is a stonefly primarily associated with clean, cool,
running water. The snowfly has been documented only in two Colorado streams: Young Gulch
and Elkhorn Creek, both small tributaries of the Cache la Poudre River. Occupied habitats are
characterized by intermittent flow and a substrate of pebble, cobble, and bedrock. Suitable
habitat for Arapahoe snowfly is not present on the property and development of this project will
have no effect on the species.
Source: Esri, DigitalGlobe, GeoEye, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, AEX, Getmapping, Aerogrid, IGN, IGP, swisstopo, and the GIS User
Community ¯
0 62.5 125 250 375 500
Feet
1801 Rosen Drive, Ft. Collins CO 80528
Drawn by: LB
Date: June 29, 2016
www.habitatmanagementinc.com
Map 1. Johnston Annex Pond
REVISIONS
Wet Meadow
Emergent Marsh
Open Water
Upland Island
Quaking Aspen
Plains Cottonwood
Eastern Hackberry
Russian Olive
Weeping Willow
Peachleaf Willow
Property Boundary
Fence
is
dependent on perennial riparian habitat with relatively undisturbed grassland vegetation
interspersed with shrubs. Use of moist areas near perennial drainages has also been documented
including: intermittent and ephemeral drainages; seeps and springs; ponds; and agricultural
ditches that occur near perennial drainages or within floodplains. Suitable riparian vegetation
includes a relatively dense combination of grasses, forbs, and shrubs; a taller shrub and tree
canopy may be present. $FFRUGLQJWRWKH86):6DOOWUDSSLQJIRU3UHEOH¶VLQ)RUW&ROOLQVhas
been negative. While the property may be considered part of the overall range for the species, it
is not mapped as occupied range or critical habitat by Colorado Parks and Wildlife. The
introduced pasture vegetation in the property is also QRWVXLWDEOH3UHEOH¶VKDELWDW Based on these
habitat requirements and the negative trapping data, it is anticipated that 3UHEOH¶VGRHVQRWRFFXU
on the property and development of this project will have no effect on PUHEOH¶V
Canada Lynx. Canada lynx habitat can generally be described as moist boreal forests or
subalpine forests in the western United States that have cold, snowy winters and a high-density
snowshoe hare prey base. The predominant vegetation of boreal forest is conifer trees, primarily
species of spruce (Picea spp.) and fir (Abies spp.). Suitable habitat for lynx is not present on the
property and development of this project will have no effect on Canada lynx.
North American Wolverines. Wolverines select areas that are cold and receive enough winter
precipitation to reliably maintain deep persistent snow late into the warm season. The
UHTXLUHPHQWRIFROGVQRZ\FRQGLWLRQVPHDQVWKDWLQWKHVRXWKHUQSRUWLRQRIWKHVSHFLHV¶UDQJH
where ambient temperatures are warmest, wolverine distribution is restricted to high elevations.
Deep, persistent, and reliable spring snow cover (April 15 to May 14) is the best overall predictor
of wolverine occurrence in the contiguous United States. Suitable habitat for wolverines is not
present on the property and development of this project will have no effect on wolverines.
Lush vegetation along watercourses or
herbaceous understories in wooded areas near
water.
Potentially
suitable
No Effect
Canada Lynx
Lynx canadensis
Threatened
Moist boreal forests or subalpine forests in the
western US that have cold, snowy winters and a
high-density snowshoe hare prey base.
No No Effect
DQG:RRGKRXVH¶V toad (Bufo woodhousei),
tiger salamander (Ambystoma tigrinum), and the plains garter snake (Thamnophis radix). Less
common riparian species include the common garter snake (Thamnophis sirtalis), wandering