Hawaiian Hoary Bat (Lasiurus cinereus semotus)
Hawaiian
Hoary Bat (Lasiurus cinereus semotus)- Ainsley Henderson
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Source: https://goo.gl/images/sRPqtF |
Physical Illustration and Ecology
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The Hawaiian Hoary Bat weighs
anywhere from 0.5-0.8 ounces and is considered to be medium sized. The name “hoary”
comes from the description of their fur, being thick and a mix of grey tinged
with white and brown tones. The Hoary possesses short ears, thick and rounded,
and edged with black. Compared to other North American subspecies (Tomich
1986c), their fur is visibly redder and are 45 percent smaller than the other
Hoary bats (Jacobs 1993a). The Hoary bat is one of three recognized hoary bat
subspecies; Lasiurus cinereus cinereus occurs throughout North America, and
Lasiurus cinereus vilosissimus occurs in South America. The Hawaiian Hoary bat
is endemic to the Hawaiian Islands and considered to be from North America,
along with the conclusion that the Hawaiian is a sub specific status to the
North American.
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Source: https://www.bikemaui.com/hawaiian-hoary-bat/ |
The
ecological study shows the Hawaiian Hoary are solitary and roost in foliage
among trees. They are found to leave their roost before sunset and return at
midnight. Hoary have also been observed to forage in a variety of both open and
more vegetatively cluttered
habitats, including over lava flows, near the ocean, in open fields, and
streams and ponds. Pregnant bats have
been found on Hawaii and Kaui and tend to breed frequently between September
and December, with the birth of young occurring in May or June.
Geographic and Population Changes
The
Hawaiian hoary bat may reside in Hawaii, Kauai and Maui, but is known to be
from Hawaii, Maui, Oahu, Kauai, and Molokai. The largest populations are known
to be on Kauai and Hawaii, estimating from hundreds to a few thousand. No
studies have been directly made towards the population size, but the number
comes from an educated estimate. The observation of the Hawaiian hoary shows
their dwelling between sea level and 7,500 feet elevation. What a range! They are
seen in both dry and wet lands, but tend to dwell in drier areas. Some were
seen to migrate from Oahu, Maui and Molokai to just Maui.
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Source:https://ecos.fws.gov/docs/recovery_plan/980511b.pdf |
Listing
and Type of Listing
On
October 13, 1970 (U.S. Fish and Wildlife Service) listed the Hawaiian hoary as
an endangered species. There is currently no population number for the bat,
because the decline has been so large and there is a lack of research. The cause of the decreased number significantly
on Oahu may be due to deforestation. There is also knowledge of pesticides,
predation and roost disturbance. However, the biggest disturbance is the
availability of roost sites making the species have no source of shelter.
Cause
of Listing and Main Threats to Its Continued Existence
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The
main threats of the Hawaiian Hoary Bat (‘ope ‘ ape ‘ a) occurred on Oahu as
the island has an increased population size. All threats include deforestation
and predation, to collisions with wind turbines and barbed wire fences. The bat
had lived on earth at one point without human influence, so they have been
greatly affected. Along with an increase in pesticides, nonnative insects have altered
their prey availability, causing a decrease in food. Lastly, they are affected by
the “white nose syndrome” that is caused by the fungus Geomyces destructans. The Hawaiian Hoary being endemic to the Hawaiian
Islands makes this risk even greater.
Source:
https://www.researchgate.net/figure/13-A-dead-hoary-bat-found-beneath-a-turbine-showing-no-visible-sign-of-injury-Photo-by_fig3_262915463
Description of Recovery Plan
Main Strategy: The first step to begin
recovery of the Hawaiian Hoary Bat is research. The information available
regarding the bat is somewhat limited, resulting in a lack of actions that can
be taken to move towards helping this species. By surveying the bat and
monitoring techniques to be applied to the population on Kauai, Maui and other
islands there can be more information on monitoring population sizes.
Finalizing the research will establish the abundance and distribution of the
Hoary and provide information on roosting habitat and food habits. Management
actions could then include addressing the threats to roosting areas to keep the
Hoary’s resources abundant. Also, by reducing predation and pesticide impacts
the bat can have an increased food resource.
Overall Goal: By completing actions in the
main strategy the species could one day be downgraded from the endangered to
the threatened list. Eventually the Bat could be delisted altogether. However,
this cannot happen without first addressing the lack of knowledge on the
species.
1. Conduct
research
needed for the conservation of the Hawaiian Hoary Bat.
a. Begin a survey and monitor
needs to determine bat distribution and amount on the Hawaiian Islands.
i. Dictate roosting habitat
associations.
ii. Dictate annual natural history
cycle.
iii. Dictate food routines.
2. Guard
and control
real time populations and detect threats.
a. Detect and evaluate threats.
b. Control threats.
c. Guard roosting areas.
d. Keep predators away.
e. Remove pesticides from
environment.
3. Educate the public.
4. Future: Revise recovery plan if
necessary and continue research of the Hawaiian Islands.
Source:
https://www.pacificrimconservation.org/wp-content/uploads/2013/10/Hawaiian%20Hoary%20Bat.pdf
What
can YOU DO?
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The
Hawaiian Hoary Bat is on the road to recovery, but are still threatened by the
world around them. YOU can help by educating yourself or getting involved in an
education program to learn more about this subspecies. Along with being
educated you can reduce pesticides used
in your day to day, stay away from roosting, and foraging areas to protect their
homes. If you would like to learn more about to Hawaiian hoary bat to help them
not only survive but thrive visit the following website http://dlnr.hawaii.gov/wildlife/esrc/hhb/.
Let’s help the one and only bat on Hawaii live!
Other
Resources
If you would like to learn anymore information covered in this
blog or explore more about saving this incredible species, feel free to click
any of the following links:
Nice blog! I didn't realize how small bats were. .5 ounces seems small but that's just medium sized. It's crazy that they are being killed from collisions from wind turbines, I didn't even think of that as a threat. Sad that that there is no research done on them, especially because they're an endemic species.
ReplyDelete- Gina Harris
I like how you organized the recovery plan into the main strategy and the break down of how this will be executed. Interesting that turbines are harming this species population and the white nose syndrome which we learned about in class. Good blog!
ReplyDelete-Emily Holloway
I think its super interesting that wind turbines and barbed wire fences are acting as a hazard for these bats. Since they're so tiny you can see why they would be so defenseless.
ReplyDelete-Cierra Heiland
I had no idea that wind turbines and wires fences would even be threat to the owls. I think that the Recovery plan is organized very well. I like the picture of how much everything will cost and what exactly the money is for.
ReplyDelete-Julia Galvan
It sucks that they are native to Maui since it is such a small are and that definitely does not help them in terms of the species health.
ReplyDelete-Dean Harris
Awww they're cute! So sad that things like wind turbines and fences are blocking their natural wild habits. The white nose syndrome info was sad too, I didn't know that fungus would effect island bats as well as mainland species. -Erin Ichimura
ReplyDeleteWhat an informative post!! Hopefully conservationist will find a way to deal with the threats to the Hoary's roosting areas and reduce predation and pesticide factors that limit the bat's food resources.-Elisabeth Huetter
ReplyDelete