Fresno Kangaroo Rat - Alijah Maldonado
FRESNO
KANGAROO RAT
Description and Ecology
The Fresno kangaroo rat, also known as Dipodomys
nitratoides exilis, is one of three subspecies of the San Joaquin kangaroo rat.
The San Joaquin kangaroo rat is distinguished as one of the smallest species of
kangaroo rat, with the Fresno kangaroo rat being the smallest of the three
subspecies, averaging at around nine inches in length. The Fresno kangaroo rat
is also distinguishable by the presence of four toes on its hind legs, comparable
to other species within the same geographic range, all of which have five toes.
The Fresno kangaroo rat has several
features that enable it to be better equipped for survival in an arid environment
and aid in its bipedal movement which include elongated hind limbs, a
long, tufted tail for balance, a shortened neck, and a comparatively large head.
It is also
equipped with short, stout claws designed for digging burrows.
The burrows dug
by Fresno kangaroo rats act as both a food storage and a nesting ground. The Fresno
kangaroo rat feeds primarily on seeds which it stores in its cheeks for
transportation back to the burrow. The species is nocturnal, and therefore does
most of its seed gathering shortly after sunset. Fresno kangaroo rats can breed
in burrows up to three times a year, having litters of up to five young.
Geographic
and Population Changes
The
current populations of Fresno kangaroo rats reside in generally the same geographic
historical areas, but on a much smaller scale. The range of the species currently
encompasses part of the San Joaquin Valley and adjacent valleys, from the
valley floor in Merced County, south of the Merced and San Joaquin rivers, to
the southern edge of the valley, and the Panoche Valley in eastern San Benito
County, the Carrizo Plain in San Luis Obispo County, and the upper Cuyama
Valley part of San Luis Obispo and Santa Barbara counties.
While
historic populations have proven difficult to determine, it is believed that
the current adult population is somewhere in the 100,000s. While the population
has sprung back from endangerment, it is believed that their numbers are currently
on the decline once again. The current population of Fresno kangaroo rats is
thought to be made up of relatively small local populations spread out across
their geographic range.
Listing Date and Type of Listing
According to the U.S. Fish and Wildlife service, the Fresno kangaroo rat
was initially listed as endangered in 1985; however, an active recovery plan
was not put in place until 1998. The recent 5-year review of the species conducted by the U.S. Fish and
Wildlife concluded that the species should still be listed as endangered.
Cause
of Listing and Main Threats
The
main cause for the decline of the Fresno kangaroo rat comes from the loss and
fragmentation of its habitat. Its current known habitat consists of three primary
fragmented areas in the Fresno area encompassing approximately 5,920 hectares. The
fragmentation of their habitat is largely a result of agricultural development,
along with additional damages caused by urbanization, transportation
infrastructure, and invasion by exotic grasses.
Isolation
and fragmentation still act as a major threat to current populations of Fresno
kangaroo rats, making it difficult for low, local populations to recolonize and
repopulate. The other main concern for current populations comes as a result of
excessive precipitation that causes flooding of crucial habitat areas. These
floods have been known to cause temporary extirpation of the Fresno kangaroo
rat in several areas; fortunately, most of these areas have been able to recover
a steady population with recolonization from surrounding local populations.
However, the regrowth of extirpated populations is becoming alarmingly more
unlikely as habitats become increasingly sparse and fragmented.
Recovery
Plan
1. Learning
the genetic relationships among extant isolated and scattered populations of San Joaquin kangaroo rats.
2.Solidifying
the known location and size of any extant Fresno kangaroo rat populations
Based upon
these three goals, the U.S Fish and Wildlife Service has created and
implemented a 12-step plan to aid Fresno kangaroo rats. The beginning steps of
the plan include identifying populations of the species and identifying the
relationships and taxonomic identities of these populations. Because habitat
loss is such a prominent threat, most of the remaining steps consist of
restoring and protecting certain areas of land to create habitat for the species.
Once enough habitat has been created, Fresno kangaroo rats will be reintroduced
into these newly created areas, and their population and habitat will continue
to be managed and monitored.
Education can also
have a crucial part in the survival of the Fresno kangaroo rat, along with
countless other species. Learning how to be more aware of how are actions
affect our environment and learning how to be less invasive in our environment
can make a huge difference in the health of all wildlife.
Other
Resources
Listed below are several helpful links to further your knowledge of the Fresno kangaroo rat.
https://www.epa.gov/endangered-species/endangered-species-save-our-species-information-fresno-kangaroo-rat
https://naturalhistory.si.edu/mna/image_info.cfm?species_id=72
https://www.arkive.org/san-joaquin-kangaroo-rat/dipodomys-nitratoides/
Image Sources
Works
Cited
“I. Fresno Kangaroo Rat (Dipodomys nitratoides exilis).” Endangered Species Recovery Program, esrp.csustan.edu/publications/pubhtml.php?doc=sjvrp&file=chapter02I00.html.
“Species Profile for Fresno kangaroo rat (Dipodomys nitratoides exilis).” ECOS Environmental Online Conservation System, U.S. Fish and Wildlife Service, ecos.fws.gov/ecp0/profile/speciesProfile?sId=5150#crithab.
Description and Ecology
The Fresno kangaroo rat, also known as Dipodomys
nitratoides exilis, is one of three subspecies of the San Joaquin kangaroo rat.
The San Joaquin kangaroo rat is distinguished as one of the smallest species of
kangaroo rat, with the Fresno kangaroo rat being the smallest of the three
subspecies, averaging at around nine inches in length. The Fresno kangaroo rat
is also distinguishable by the presence of four toes on its hind legs, comparable
to other species within the same geographic range, all of which have five toes. The Fresno kangaroo rat has several features that enable it to be better equipped for survival in an arid environment and aid in its bipedal movement which include elongated hind limbs, a long, tufted tail for balance, a shortened neck, and a comparatively large head.
The burrows dug by Fresno kangaroo rats act as both a food storage and a nesting ground. The Fresno kangaroo rat feeds primarily on seeds which it stores in its cheeks for transportation back to the burrow. The species is nocturnal, and therefore does most of its seed gathering shortly after sunset. Fresno kangaroo rats can breed in burrows up to three times a year, having litters of up to five young.
Geographic
and Population Changes
The collective studies of several scientists
over time have shown that historically, Fresno kangaroo rats were found in an
approximated 359,700 hectare area in California. The area is thought to have
included a large area of grassland on the San Joaquin Valley floor. However,
habitat loss and fragmentation has drastically reduced their geographic range.
The
current populations of Fresno kangaroo rats reside in generally the same geographic
historical areas, but on a much smaller scale. The range of the species currently
encompasses part of the San Joaquin Valley and adjacent valleys, from the
valley floor in Merced County, south of the Merced and San Joaquin rivers, to
the southern edge of the valley, and the Panoche Valley in eastern San Benito
County, the Carrizo Plain in San Luis Obispo County, and the upper Cuyama
Valley part of San Luis Obispo and Santa Barbara counties.
While
historic populations have proven difficult to determine, it is believed that
the current adult population is somewhere in the 100,000s. While the population
has sprung back from endangerment, it is believed that their numbers are currently
on the decline once again. The current population of Fresno kangaroo rats is
thought to be made up of relatively small local populations spread out across
their geographic range.
Listing Date and Type of Listing
According to the U.S. Fish and Wildlife service, the Fresno kangaroo rat
was initially listed as endangered in 1985; however, an active recovery plan
was not put in place until 1998. The recent 5-year review of the species conducted by the U.S. Fish and
Wildlife concluded that the species should still be listed as endangered.
Cause of Listing and Main Threats
Cause of Listing and Main Threats
The
main cause for the decline of the Fresno kangaroo rat comes from the loss and
fragmentation of its habitat. Its current known habitat consists of three primary
fragmented areas in the Fresno area encompassing approximately 5,920 hectares. The
fragmentation of their habitat is largely a result of agricultural development,
along with additional damages caused by urbanization, transportation
infrastructure, and invasion by exotic grasses.
Isolation
and fragmentation still act as a major threat to current populations of Fresno
kangaroo rats, making it difficult for low, local populations to recolonize and
repopulate. The other main concern for current populations comes as a result of
excessive precipitation that causes flooding of crucial habitat areas. These
floods have been known to cause temporary extirpation of the Fresno kangaroo
rat in several areas; fortunately, most of these areas have been able to recover
a steady population with recolonization from surrounding local populations.
However, the regrowth of extirpated populations is becoming alarmingly more
unlikely as habitats become increasingly sparse and fragmented.
Recovery
Plan
The U.S. Fish and Wildlife Service has created a recovery plan determined
to bring the Fresno kangaroo rat off the endangered list. The proposed plan is
guided by three integral topics that the US Fish and Wildlife Service believe are
key to the restoration of the species.
1. Learning
the genetic relationships among extant isolated and scattered populations of San Joaquin kangaroo rats.
2.Solidifying
the known location and size of any extant Fresno kangaroo rat populations
3. Learning
how to manage natural lands to enhance habitat for Fresno kangaroo rats
Based upon
these three goals, the U.S Fish and Wildlife Service has created and
implemented a 12-step plan to aid Fresno kangaroo rats. The beginning steps of
the plan include identifying populations of the species and identifying the
relationships and taxonomic identities of these populations. Because habitat
loss is such a prominent threat, most of the remaining steps consist of
restoring and protecting certain areas of land to create habitat for the species.
Once enough habitat has been created, Fresno kangaroo rats will be reintroduced
into these newly created areas, and their population and habitat will continue
to be managed and monitored.
What
can you do?
Fresno
kangaroo rats need all the help they can get if they are ever to fully recover
in the wild. Each individual plays a role in preserving our environment and the
species we share it with. As stated, habitat loss is the single biggest current
threat to the Fresno kangaroo rat, so taking actions such as protesting against
the expansion of agricultural development in the Fresno area or sending a
letter to a local official explaining why certain areas in the Fresno area need
to be preserved could play a key role in the survival of the Fresno kangaroo
rat.
Other
Resources
Listed below are several helpful links to further your knowledge of the Fresno kangaroo rat.
https://www.epa.gov/endangered-species/endangered-species-save-our-species-information-fresno-kangaroo-rat
https://naturalhistory.si.edu/mna/image_info.cfm?species_id=72
https://www.arkive.org/san-joaquin-kangaroo-rat/dipodomys-nitratoides/
Image Sources
http://www.mammalwatching.com/Nearctic/Images/California/Giant%20Kangaroo%20Rat.jpg
http://bio227-4spring2015.blogspot.com/2015/06/the-fresno-kangaroo-rat-by-sara-grunwald.html
Works
Cited
“Dipodomys nitratoides .” The IUCN Red List of Threatened Species, www.iucnredlist.org/details/6683/0.
“I. Fresno Kangaroo Rat (Dipodomys nitratoides exilis).” Endangered Species Recovery Program, esrp.csustan.edu/publications/pubhtml.php?doc=sjvrp&file=chapter02I00.html.
“Species Profile for Fresno kangaroo rat (Dipodomys nitratoides exilis).” ECOS Environmental Online Conservation System, U.S. Fish and Wildlife Service, ecos.fws.gov/ecp0/profile/speciesProfile?sId=5150#crithab.
It surprised me that the population of the Fresno Kangaroo Rat had increased but is now in decline again. I like how you brought attention to the fact that these animals still need our help even though their population had increased in the past. Staying aware was one of your key points of things that we can do to help, and that is definitely something that I will do! - Anna Luehrs
ReplyDeleteFirst off, the Fresno Kangaroo Rat is so cute... I never even knew they existed! Also, I would have never expected flooding to be a cause of their endangerment, but I guess it makes sense because they're such small creatures. I like how you point out that education is an important step to their recovery. - Ava Mattis
ReplyDeleteIt's interesting to learn about a creature that is so close to home for me. It's unfortunate to see human development and agriculture affecting their habitat. Hopefully relocation of these animals can help these populations as it is quite unlikely that Fresno will stop expanding its agricultural productions! -Brooke Lochhead
ReplyDeleteawww! they are super cute and tiny! It is so sad that habitat destruction and fragmentation has had such a negative impact on these small creatures. Overall your blog was really organized, clear and easy to understand
ReplyDelete_Shea Menzel
The name kangaroo rat is great; they are so cute. It's really cool how close these are to Cal Poly (& for me, home). It sucks that they are once again on the decline. Your blog is well organized too, I love the pictures! - Hannah Lee
ReplyDeleteI like that you chose to write about a species that exists in the San Luis Obispo County, because it makes the problem feel closer to home and could help people realize that it extinction is a real problem that is prevalent everywhere and not just in some far away place where they don't feel like there can be something to be done. - Ashley Lam
ReplyDeleteI don’t think I’ve ever been excited to learn about a rat, but the Fresno Kangaroo Rat is really cute. My curiosity is, what is leading to the springing and then declining of the population? It’s saddening that when one good thing is happening, a bad thing is happening as well, for example more rain benefits us, but not the Fresno Kangaroo Rat. - Samary Mayo
ReplyDeleteHonestly I am for sure not a rat person but this specific rat rates higher on my list than most. I enjoyed how you chose a species that presides in our college town, that was very interesting. Also, your blog was in a very organized manner and very understandable. - Scott Martin
ReplyDelete