The Biota of the Gordon Natural Area - Mammals

Until recently, mammal ‘research’ at the Gordon consisted of a checklist of mammal observations and trail camera images that was compiled by GNA staff. Despite this absence of focused research, the White-tailed Deer is one of the most commonly encountered animals at the GNA (perhaps second only to deer ticks) and deer have had profound effects on the flora of the GNA (primarily through overgrazing and selective grazing).

Beginning in 2019, Temple University Doctoral candidate Payton Phillips has included the Gordon as a study site in her investigation of wildlife and tick-borne diseases. Through this work, she has added one new mammal species, the Southern Flying Squirrel (Glaucomys volans ) to the GNA checklist and has also provided photographic confirmation of other mammals that we only ‘knew’ from their tracks (e.g., Raccoons) and/or from the leavings of prey that they had killed (e.g., from deer carcasses left by Coyotes).

To date, 14 species of mammals, in 13 Genera, 9 Families, and 5 Orders, have been noted at the GNA. It is worth noting that many of these species are ‘subsidized predators’: i.e., species (predators and scavengers) with broad-based diets whose population density is elevated by human-facilitated resources (e.g., garbage, etc.). These elevated populations then can potentially ‘spill over’ into adjacent, non-developed areas (in this case, the Gordon), thereby exerting undo pressure on the ecosystem.

You can explore the mammal checklist below, or you can access a pdf copy of the checklist.

Canis familiaris (Domestic Dog)

Group: Mammals

Family: Canidae

Notes

Common Names: Domestic Dog

Year Observed: 2020

Identified and First Noted By: Nur Ritter

Notes:

Although this species has long been noted in the GNA, it was never considered to be part of the fauna. However, once a skull was noted in Area G1N on 9-22-20, it was considered to be a member of the GNA biota.

iNaturalist Observations:

60457549 (Observed: 9/22/2020)

Images

Canis familiaris (Domestic Dog)
Canis familiaris (Domestic Dog)
Canis familiaris (Domestic Dog)

Canis latrans (Coyote)

Group: Mammals

Family: Canidae

Notes

Common Names: Coyote

Years Observed: 2020; 2022; 2023; 2024

Identified By: Payton Phillips

First Noted By: Wildlife Camera

Also Noted By: Anna Carlson; Nur Ritter (tracks)

Notes:

For a number of years, we suspected that Coyotes were present in the Gordon because we repeatedly found the remains of dead fawns that had been dismembered and carried far from the killing site. Finally, in 2020, Temple University Doctoral student Payton Phillips came up with a verified Coyote sighting from one of her trail cameras. Then, in 2022, Temple U. Masters' student Anna Carlson came up with a trail cam photo of a second Coyote. Since, that time, GNA Staff have come across two sets of Coyote tracks and GNA trail cameras have recorded videos of coyotes in various parts of the GNA.

iNaturalist Observations:

148690747 (Observed: 2/2/2023)

147479252 (Observed: 1/27/2023)

GNA YouTube Videos featuring the Coyote:

Coyotes kill doe (and the week that follows) (Video Posted: 3/29/2024)

Trailcam: Geologists meet Coyote (Video Posted: 02/13/2024)

Coyote in the Gordon woods at night (Video Posted: 05/12/2023)

Coyotes kill doe (and the week that follows) (Video Posted: 2/29/2024)

Images

Canis latrans (Coyote)
Canis latrans (Coyote)
Canis latrans (Coyote)
Canis latrans (Coyote)
Canis latrans (Coyote)
Canis latrans (Coyote)

Vulpes vulpes (Red Fox)

Group: Mammals

Family: Canidae

Notes

Common Names: Red Fox

Years Observed: 2008; 2010; 2016; 2017; 2018; 2019; 2020; 2021; 2022; 2023; 2024

Identified and First Noted By: Gerry Hertel

Also Noted By: Kendra McMillin; Nur Ritter; Maribeth Beatty; Ariana Rivellini; Payton Phillips; Kathryn Krueger; Miranda Davies; Wildlife Camera(s)

Notes:

Often seen at the Gordon, and there have been various years when kits have been observed. Food sources in surrounding properties allow for a greater than normal number of Red Foxes in the GNA.

iNaturalist Observations:

150728759 (Observed: 3/8/2023)

149426876 (Observed: 2/22/2023)

148691409 (Observed: 2/3/2023)

147284352 (Observed: 1/11/2023)

GNA YouTube Videos featuring the Red Fox:

Coyotes kill doe (and the week that follows) (Video Posted: 3/29/2024)

Trailcam: Fox vs. Heron II 🦊 (Video Posted: 02/20/2024)

Red Fox ponders eating a Great Blue Heron (Video Posted: 11/03/2023)

Fox Leaping at night in the rain (Video Posted: 09/18/2023)

What Does The Fox Say? — Fox calling alongside Plum Run. (Video Posted: 06/27/2023)

Red Fox kit being homeschooled (Video Posted: 06/11/2023)

Two Red Fox kits exploring around their den at night. (Video Posted: 06/06/2023)

Red Fox surveying along the Cattail Swamp (Video Posted: 05/01/2023)

Red Fox crossing Plum Run (Video Posted: 03/08/2023)

Images

Vulpes vulpes (Red Fox)
Vulpes vulpes (Red Fox)
Vulpes vulpes (Red Fox)
Vulpes vulpes (Red Fox)
Vulpes vulpes (Red Fox)
Vulpes vulpes (Red Fox)
Vulpes vulpes (Red Fox)

Castor canadensis (American Beaver)

Group: Mammals

Family: Castoridae

Notes

Common Names: American Beaver

Year Observed: 2022

Identified By: Thomas W. French (iNaturalist)

First Noted By: N. Ritter

Notes:

To date, known for the Gordon only from a skull that was found near to the Route 202 ramp in the spring of 2022 during the construction of a new trail. Our guess is that this individual may have traveled from Brandywine Creek (where there are known populations of American Beavers), up Plum Run, and onto Gordon Run. It would have encountered the Route 202 ramp at the upper end of Gordon Run and may have either been hit by a vehicle or just expired in the Gordon. Alternatively, the skull may have been dropped over the Gordon by a raptor (no bones other than the skull were found), or died elsewhere in the Gordon or surrounding area and was carried to where it was found by a scavenger.

iNaturalist Observations:

118550595 (Observed: 5/24/2022)

Images

Castor canadensis (American Beaver)
Castor canadensis (American Beaver)
Castor canadensis (American Beaver)
Castor canadensis (American Beaver)

Odocoileus virginianus (White-tailed Deer)

Group: Mammals

Family: Cervidae

Notes

Common Names: White-tailed Deer

Years Observed: 2007; 2008; 2009; 2010; 2011; 2012; 2013; 2014; 2015; 2016; 2017; 2018; 2019; 2020; 2021; 2022; 2023; 2024

Identified and First Noted By: William Overlease

Also Noted By: Gerry Hertel; Harry Tiebout; Jessica Schedlbauer; Greg Turner; Kendra McMillin; Nur Ritter; Alexandra Hodowanec; Kate Thompson; Paige Vermeulen; Maribeth Beatty; Jared Kline; Ariana Rivellini; Noah Long; Payton Phillips; Maeve Dowd; Maddison Rettenmaier; Kathryn Krueger; Miranda Davies; Alex Desjardines; Jessica Greulich; James Simpson (and, undoubtedly, many others); Wildlife Camera(s)

Notes:

The GNA is inhabited by a white-tailed deer population that is approximately 4-8 times its carrying capacity. This high population results in significant over-browsing and appears to be driving a transition in the GNA towards plant species that are resistant to browsing.

iNaturalist Observations:

137661784 (Observed: 10/5/2022)

83943509 (Observed: 6/21/2021)

70339958 (Observed: 2/28/2021)

GNA YouTube Videos featuring the White-tailed Deer:

Coyotes kill doe (and the week that follows) (Video Posted: 3/29/2024)

Deer Browsing Fungi #trailcam #deer (Video Posted: 03/05/2024)

Deer vs Tree Cage #shorts (Video Posted: 02/12/2024)

Deer in a bamboo grove at the GNA (Video Posted: 07/18/2023)

Some Wild and Crazy Deer (Video Posted: 05/12/2023)

Images

Odocoileus virginianus (White-tailed Deer)
Odocoileus virginianus (White-tailed Deer)
Odocoileus virginianus (White-tailed Deer)
Odocoileus virginianus (White-tailed Deer)

Peromyscus leucopus (White-footed Mouse)

Group: Mammals

Family: Cricetidae

Notes

Common Names: White-footed Mouse

Years Observed: 2011; 2021; 2023

Identified and First Noted By: Gerry Hertel

Also Noted By: Nur Ritter; Miranda Davies; Wildlife Camera(s)

Notes:

A primary carrier of Lyme Disease bacteria.

iNaturalist Observations:

68608187 (Observed: 1/25/2021)

Images

Peromyscus leucopus (White-footed Mouse)
Peromyscus leucopus (White-footed Mouse)
Peromyscus leucopus (White-footed Mouse)

Didelphis virginiana (Opossum)

Group: Mammals

Family: Didelphidae

Notes

Common Names: White-tailed Deer

Years Observed: 2007; 2008; 2009; 2010; 2011; 2012; 2013; 2014; 2015; 2016; 2017; 2018; 2019; 2020; 2021; 2022; 2023; 2024

Identified and First Noted By: William Overlease

Also Noted By: Gerry Hertel; Harry Tiebout; Jessica Schedlbauer; Greg Turner; Kendra McMillin; Nur Ritter; Alexandra Hodowanec; Kate Thompson; Paige Vermeulen; Maribeth Beatty; Jared Kline; Ariana Rivellini; Noah Long; Payton Phillips; Maeve Dowd; Maddison Rettenmaier; Kathryn Krueger; Miranda Davies; Alex Desjardines; Jessica Greulich; James Simpson (and, undoubtedly, many others); Wildlife Camera(s)

Notes:

The GNA is inhabited by a white-tailed deer population that is approximately 4-8 times its carrying capacity. This high population results in significant over-browsing and appears to be driving a transition in the GNA towards plant species that are resistant to browsing.

iNaturalist Observations:

137661784 (Observed: 10/5/2022)

83943509 (Observed: 6/21/2021)

70339958 (Observed: 2/28/2021)

GNA YouTube Videos featuring the White-tailed Deer:

Coyotes kill doe (and the week that follows) (Video Posted: 3/29/2024)

Deer Browsing Fungi #trailcam #deer (Video Posted: 03/05/2024)

Deer vs Tree Cage #shorts (Video Posted: 02/12/2024)

Deer in a bamboo grove at the GNA (Video Posted: 07/18/2023)

Some Wild and Crazy Deer (Video Posted: 05/12/2023)

Images

Didelphis virginiana (Opossum)

Felis catus (Feral Cat)

Group: Mammals

Family: Felidae

Notes

Common Names: Feral Cat

Year Observed: 2023

Identified By: Nur Ritter

First Noted By: Wildlife Camera

Sylvilagus floridanus (Eastern Cottontail)

Group: Mammals

Family: Leporidae

Notes

Common Names: Eastern Cottontail

Years Observed: 2016; 2017; 2018; 2019; 2020; 2021; 2022; 2023; 2024

Identified and First Noted By: Kendra McMillin

Also Noted By: Gerry Hertel; Nur Ritter; Paige Vermeulen; Maribeth Beatty; Noah Long; Miranda Davies; Kathryn Krueger; David Kramer; Wildlife Camera(s)

Images

Sylvilagus floridanus (Eastern Cottontail)

Mephitis mephitis (Striped Skunk)

Group: Mammals

Family: Mephitidae

Notes

Common Names: Striped Skunk

Years Observed: 2019; 2021; 2023; 2024

Identified By: Nur Ritter

First Noted By: Nur Ritter (by scent)

Also Noted By: Wildlife Camera

Notes:

For many years, the presence of Striped Skunks in the Gordon was based on its scent. However, in 2023 we began seeing this species on trail camera images.

iNaturalist Observations:

186087593 (Observed: 10/2/2023)

Images

Mephitis mephitis (Striped Skunk)

Rattus norvegicus (Brown Rat)

Group: Mammals

Family: Muridae

Notes

Common Names: Brown Rat

Years Observed: 2018; 2023; 2024

Identified and First Noted By: Jared Kline

Also Noted By: Miranda Davies; Nur Ritter; Wildlife Camera

iNaturalist Observations from the GNA:

169829414 (Observed: 6/20/2023)

Images

Rattus norvegicus (Brown Rat): Brown Rat nestling
Rattus norvegicus (Brown Rat)
Rattus norvegicus (Brown Rat)
Rattus norvegicus (Brown Rat): close-up of mouth
Rattus norvegicus (Brown Rat): close-up of forefoot
Rattus norvegicus (Brown Rat): close up of hind foot

Lontra canadensis (North American River Otter)

Group: Mammals

Family: Mustelidae

Notes

Common Names: North American River Otter

Year Observed: 2024

Identified By: Nur Ritter

First Noted By: Wildlife Camera

iNaturalist Observations from the GNA:

209302055 (Observed: 4/23/2024)

GNA YouTube Videos featuring the North American River Otter:

Otter in the GNA (Video Posted: 4/25/2024)

Images

Lontra canadensis (North American River Otter)
Lontra canadensis (North American River Otter)
Lontra canadensis (North American River Otter)
Lontra canadensis (North American River Otter)
Lontra canadensis (North American River Otter)

Neogale vison (American Mink)

Group: Mammals

Family: Mustelidae

Notes

Common Names: American Mink

Years Observed: 2022; 2024

Identified and First Noted By: David Kramer

Also Noted By: Wildlife Camera; Kevin Murtaugh

Notes:

Kevin Murtaugh—a long-time visitor to the Gordon—reported having seen a mink in the meadow in the eastern GNA in 2024.

iNaturalist Observations from the GNA:

202441066 (Observed: 3/13/2024)

GNA YouTube Videos featuring the American Mink:

#trailcam Mink & Groundhog in the stream (Video Posted: 3/15/2024)

Minks and Groundhog in water (Video Posted: 3/28/2024)

Images

Neogale vison (American Mink)
Neogale vison (American Mink): Swimming across Plum Run
Neogale vison (American Mink): Close-up of an American Mink entering the water (Plum Run)
Neogale vison (American Mink): Close-up of an American Mink entering the water (Plum Run)
Neogale vison (American Mink): Close-up of an American Mink beginning to swim across Plum Run

Procyon lotor (Raccoon)

Group: Mammals

Family: Procyonidae

Notes

Common Names: Raccoon

Years Observed: 2008; 2011; 2019; 2020; 2022; 2023; 2024

Identified and First Noted By: Kendra McMillin

Also Noted By: Payton Phillips; Nur Ritter; Kathryn Krueger (tracks); Wildlife Camera(s)

iNaturalist Observations:

194454494 (Observed: 12/20/2023)

148691089 (Observed: 2/3/2023)

148401882 (Observed: 2/9/2023)

147478068 (Observed: 1/27/2023)

110836027 (Observed: 4/8/2022)

GNA YouTube Videos featuring the Raccoon:

What if a tree falls in the forest and nobody's there to hear it (except a trail cam)? (Video Posted: 08/28/2023)

Raccoon Stampede!!! (Video Posted: 07/25/2023)

Raccoon Conga Line (Video Posted: 07/20/2023)

Raccoon having a drink (Video Posted: 05/19/2023)

Images

Procyon lotor (Raccoon)

Glaucomys volans (Southern Flying Squirrel)

Group: Mammals

Family: Sciuridae

Notes

Common Names: Southern Flying Squirrel

Years Observed: 2019; 2023

Identified By: Payton Phillips

First Noted By: Wildlife Camera

Notes:

Noted during Tick-borne Disease monitoring by Peyton Phillips (Integrative Ecology Lab, Temple University, Philadelphia, PA).

iNaturalist Observations:

68926242 (Observed: 11/23/2019)

Images

Glaucomys volans (Southern Flying Squirrel)

Marmota monax (Groundhog)

Group: Mammals

Family: Sciuridae

Notes

Common Names: Groundhog

Years Observed: 2019; 2022; 2023; 2024

Identified and First Noted By: Nur Ritter

Also Noted By: Miranda Davies; Kathryn Krueger; Jessica Greulich; Wildlife Camera(s)

iNaturalist Observations:

149429630 (Observed: 2/22/2023)

112148362 (Observed: 4/14/2022)

GNA YouTube Videos featuring the Groundhog:

#trailcam Mink & Groundhog in the stream (Video Posted: 3/15/2024)

Groundhog Cliffhanger!!! (Video Posted: 08/21/2023)

Images

Marmota monax (Groundhog)
Marmota monax (Groundhog)

Sciurus carolinensis (Eastern Gray Squirrel)

Group: Mammals

Family: Sciuridae

Notes

Common Names: Eastern Gray Squirrel

Years Observed: 2008; 2010; 2016; 2017; 2018; 2019; 2020; 2021; 2022; 2023; 2024

Identified and First Noted By: Kendra McMillin

Also Noted By: Wildlife Camera(s); Gerry Hertel; Nur Ritter; Paige Vermeulen; Payton Phillips; Noah Long; Kathryn Krueger; Miranda Davies; and, countless others

iNaturalist Observations:

180020493 (Observed: 8/24/2023)

151061080 (Observed: 3/13/2023)

99625614 (Observed: 10/28/2021)

GNA YouTube Videos featuring the Eastern Gray Squirrel:

Discretion is the Better Part of Valor: Squirrel checks out Hawk (Video Posted: 10/18/2023)

What if a tree falls in the forest and nobody's there to hear it (except a trail cam)? (Video Posted: 08/28/2023)

Images

Sciurus carolinensis (Eastern Gray Squirrel)

Tamias striatus (Eastern Chipmunk)

Group: Mammals

Family: Sciuridae

Notes

Common Names: Eastern Chipmunk

Years Observed: 2022; 2023

Identified and First Noted By: Kathryn Krueger

Also Noted By: Wildlife Camera(s)

Notes:

To date: A single individual has been noted.

iNaturalist Observations:

109239154 (Observed: 3/22/2022)

Images

Tamias striatus (Eastern Chipmunk)
Tamias striatus (Eastern Chipmunk)

Tamiasciurus hudsonicus (American Red Squirrel)

Group: Mammals

Family: Sciuridae

Notes

Common Names: American Red Squirrel

Years Observed: 2019; 2021; 2022; 2023; 2024

Identified and First Noted By: Nur Ritter

Also Noted By: Paige Vermeulen; Kathryn Krueger; Wildlife Camera(s)

iNaturalist Observations:

107418358 (Observed: 2/21/2022)

107417426 (Observed: 2/10/2022)

GNA YouTube Videos featuring the American Red Squirrel:

What if a tree falls in the forest and nobody's there to hear it (except a trail cam)? (Video Posted: 08/28/2023)

Images

Tamiasciurus hudsonicus (American Red Squirrel)
Tamiasciurus hudsonicus (American Red Squirrel)
Tamiasciurus hudsonicus (American Red Squirrel)
Tamiasciurus hudsonicus (American Red Squirrel)

Blarina brevicauda (Northern Short-tailed Shrew)

Group: Mammals

Family: Soricidae

Notes

Common Names: Northern Short-tailed Shrew

Year Observed: 2023

Identified By: Nur Ritter

First Noted By: Jessica Greulich

iNaturalist Observations from the GNA:

181090927 (Observed: 8/31/2023)

Images

Blarina brevicauda (Northern Short-tailed Shrew)
Blarina brevicauda (Northern Short-tailed Shrew)

Cryptotis parvus (North American Least Shrew)

Group: Mammals

Family: Soricidae

Notes

Common Names: North American Least Shrew

Year Observed: 2024

Identified and First Noted By: Nur Ritter

iNaturalist Observations from the GNA:

204412501 (Observed: 3/29/2024)

Images

Cryptotis parvus (North American Least Shrew)
Cryptotis parvus (North American Least Shrew)
Cryptotis parvus (North American Least Shrew)
Cryptotis parvus (North American Least Shrew)

Lasiurus borealis (Eastern Red Bat)

Group: Mammals

Family: Vespertilionidae

Notes

Common Names: Eastern Red Bat

Year Observed: 2022

Identified and First Noted By: Kathryn Krueger

Notes:

A distressed individual was on Kathryn Krueger's shoe in the large ginseng enclosure in Area G1S. No other individuals were noted.

iNaturalist Observations:

112041716 (Observed: 4/19/2022)

Images

Lasiurus borealis (Eastern Red Bat)
Lasiurus borealis (Eastern Red Bat)
Lasiurus borealis (Eastern Red Bat)
Lasiurus borealis (Eastern Red Bat)