Oreohelix florida (Florida Mountainsnail)

[sebbe67]

Oreohelix florida

The New Mexico endemic Florida Mountainsnail, Oreohelix florida, is a State endangered species known as a fossil from four small, arid "sky island" mountains in southern New
Mexico. It is named after the type locality in the Florida Mountains, just southeast of the town ofDeming in Luna County. Noted malacologist H. A. Pilsbry discovered its shells there
in the 1930's at what he called "central peak", which is probably what is today known as Baldy Peak, a massive limestone outcrop in the center of the mountain range.

Prior to the surveys, the investigator obtained a collection permit from the NM Department of Game & Fish and surface geology maps of the Florida and Tres Hennanas Mountains to
target limestone formations, where this snail is thought to be an obligate. On the evening of July 30, 1997, a rainstorm lasted over two hours in the Florida Mountains. Early the next
morning, two surveyors biked to the mesic habitat at the base ofBaldy Peak, a massive limestone outcrop. A total of22 points were surveyed around the base ofBaldy Peak. No live or fossil Oreohelix individuals were found.

The only fossilized shell of Oreohelix florida found at Baldy Peak was not discovered at one of the 22 survey points. Surveyors were investigating a large limestone boulder with many embedded fossils at the base ofBaldy Peak, when one surveyor discovered the fossilized Oreohelixflorida shell under the boulder. The surveyors then completed several sample
points in this location, but no other shells were found.

On August 1, 1997, the surveyors hiked to another site adjacent to Baldy Peak where there was much limestone deposition, but less mesic habitat. Due to the arid southwest-facing
exposure, and the lack of rainfall the previous evening, this site was considerably drier than the first. Similar to the first site, only one fossilized shell of Oreohelix florida was discovered here, but it was found emoute between survey points, not during a survey. As there was no rainfall forecasted for the following days, the surveyors abandoned the efforts the evening of August 1, 1997.

Surveyors made an additional trip to the Florida Mountains on August 18, 1997, hoping to match the next survey attempt with another rain event that had been forecasted. Unfortunately, after experiencing no rainfall on August 19, and finding no other live snails foraging on limestone depositions in the xeric habitat around Gym Peak, the surveyors abandoned efforts once again.

Surveyors traveled to the University of Texas at El Paso to deposit the two fossilized Oreohe/ix shells with Dr. Art Metcalf, who has amassed the largest collection of land snails in
the southwest. Upon returning to Albuquerque, the surveyors noticed large thunderhead cloud formations congregating around the Florida Mountains, and made one last effort to camp, awaiting the rains. On August 23, 1997, the surveyors returned home with no rain events having occurred. No sites in the Tres Herrnanas Mountains were surveyed due to the unfavorable weather conditions and apparent small amount of limestone habitat shown on the geology maps.


It is the New Mexico Natural Heritage Program's opinion that Oreohelix florida is in fact extinct in the Florida Mountains. The first survey site at Baldy Peak was not only surveyed in
ideal conditions, with enough moisture present to activate landsnai1s, but is the only site in the Florida Mountains harboring enough mesic habitat to potentially support a relic population of Oreohelix florida. A future survey at that mountain is not recommended.

[another specialist]

Inventory for Oreohelix florida, a New Mexico Endemic Land snail
Progress Report
..
New Mexico Natural Heritage Program
University of New Mexico
Department of Biology
851 University Blvd. SE, Suite 101
Albuquerque, NM 87131
Investigator:
Kjmberly Score,
Research Biologist
11/17/97
Introduction
The New Mexico endemic Florida Mountainsnail, Oreohelix florida, is a State endangered
species known as a fossil from four small, arid "sky island" mountains in southern New
Mexico. It is named after the type locality in the Florida Mountains, just southeast of the
town ofDeming in Luna County. Noted malacologist H. A. Pilsbry discovered its shells there
in the 1930's at what he called "central peak", which is probably what is today known as
Baldy Peak, a massive limestone outcrop in the center of the mountain range. Pilsbry
considered that Oreohelix florida could be extant elsewhere in the Florida Mountains, but
possibly extinct at Baldy Peak.
With a few exceptions, most of the snails in the genus Oreohelix are calciphilic, inhabiting
limestone talus, where calcium is available for shell production and growth. Inside a talus
slope, land snails can regulate their temperature and the amount of exposure received by
changing the depth at which they aestivate or forage. The talus is a unique microhabitat, which
accumulates leaflitter (often from oak trees on the periphery) and other detritus, upon which
the snails will forage. Rains are of great importance because they cool off the surface of the
talus, allowing the snails to emerge and begin foraging. It is not uncommon to witness great
numbers of snails out foraging immediately after a rainstorm. Thus, it was crucial that our
survey efforts were focused in limestone talus during or immediately following a rain event.
Methods
At each limestone talus slope, the surveyors documented the location with a global positioning
system, noted the canyon, date, time, slope, aspect and dominant vegetation. The ambient
temperature and the amount of precipitation received within the days prior the survey was also
recorded. The two surveyors split the talus into halves, as to not overlap search efforts. As
each surveyor came to a suitable habitat area, defined as having enough soil and litter
accumulation around limestone rocks, the % rock, % soil, and % litter was recorded within a
lm wide by 2m long rectangle. (lm x 2m is typically enough space to survey within 5 rnin.)
A point number and start time was recorded before the surveyor began turning over rocks and
looking for snails. Rocks of small to moderate size were turned over and picked up as each
side was examined for the presence of foraging or aestivating snails. Larger rocks were
merely rolled over, as they could not be lifted. Each observer surveyed 5 minutes at each of
their respective plots.
The time elapsed from the beginning of the survey to the discovery of the first shell and the
first live individual was recorded. Surveyors continued turning deeper rocks within the Im x
2m rectangular plot for 5 minutes. At the end of the survey, the size of the rocks, litter
composition, and level of soil moisture encountered within the plot was noted. Three values
were taken to determine the variation of rock size within the plot. All measurements were
estimates of the diameter of the rocks in centimeters or in meters: 1) the diameter of the
smallest rocks in the plot (e.g. 1 centimeter in diameter), 2) the diameter of the average-sized
rocks (e.g. 15 cm diameter), and 3) the size of the largest rocks in the plot (e.g. .75 m
diameter). Soil moisture level measurements were somewhat subjective; we used the
categories "low", "moderate", and "high." The soil was picked up in the hands and
compressed together in the palms. If the soil retained its compressed shape in an open palm
then the moisture was described as "high." When the compressed soil broke down into
smaller clumps in the palm of the hand, not retaining its squeezed form, the moisture level was
described as "moderate." Ifthe soil moisture was comparatively "low" or "dry," it could not
be compacted in the hands.
One of the two surveyors used a hygrometer to determine the percent relative humidity, dew
point, and temperature within the soil. While turning rocks within a plot, the surveyor
recorded the %RH and temperature of the soil (the dew point can be inferred from a scale on
the back of the unit) as shells and live snails were found.
Photo points were usually taken from the opposite side of the canyon or a better vantage point
enabling viewers to see the majority, if not a11, of the talus slope surveyed. As a suitable
vantage point was found, a rebar was hammered into the substrate where the photographer
stood to take the picture. The bearing of the camera towards the direction of the talus slope
was determined with a compass. The roll #, picture #, and set focal length (e.g. 35-70 mm)
used in taking the picture was noted. Surveyors took a GPS position of the rebar location,
recorded the name and location of the talus slope photographed, and described the distance
and bearing to obvious landmarks near the photo point. All photos were taken with Kodak
Elite 400 slide film by a Minolta camera.
Overall Findings
Prior to the surveys, the investigator obtained a collection permit from the NM Department of
Game & Fish and surface geology maps of the Florida and Tres Hennanas Mountains to
target limestone formations, where this snail is thought to be an obligate. On the evening of
July 30, 1997, a rainstorm lasted over two hours in the Florida Mountains. Early the next
morning, two surveyors biked to the mesic habitat at the base ofBaldy Peak, a massive
limestone outcrop. A total of22 points were surveyed around the base ofBaldy Peak. No live
or fossil Oreohelix individuals were found. However, two other endemic land snails,
Ashmunella walkeri (Gl) and Sonorella hachitana (Gl), were out foraging in great numbers.
This was pleasing, not only to incorporate their occurrence records into the New Mexico
Natural Heritage Program's Biological Conservation Database, but also to confinn that the
survey was done at an ideal time (with enough moisture present in the soil to activate
aestivating snails).
The only fossilized shell of Oreohelix florida found at Baldy Peak was not discovered at one
of the 22 survey points. Surveyors were investigating a large limestone boulder with many
embedded fossils at the base ofBaldy Peak, when one surveyor discovered the fossilized
Oreohelixflorida shell under the boulder. The surveyors then completed several sample
points in this location, but no other shells were found.
On August 1, 1997, the surveyors hiked to another site adjacent to Baldy Peak where there
was much limestone deposition, but less mesic habitat. Due to the arid southwest-facing
exposure, and the lack of rainfall the previous evening, this site was considerably drier than
the first. In fact, only a few live Sonorel/a hachitana and no Ashmunel/a walkeri were
encountered on the approach to the site. A total of 6 points were surveyed, with no live snails
of any species found in the survey plots. Similar to the first site, only one fossilized shell of
Oreohelix florida was discovered here, but it was found emoute between survey points, not
during a survey. As there was no rainfall forecasted for the following days, the surveyors
abandoned the efforts the evening of August 1, 1997.
Surveyors made an additional trip to the Florida Mountains on August 18, 1997, hoping to
match the next survey attempt with another rain event that had been forecasted.
Unfortunately, after experiencing no rainfall on August 19, and finding no other live snails
foraging on limestone depositions in the xeric habitat around Gym Peak, the surveyors
abandoned efforts once again.
Surveyors traveled to the University of Texas at El Paso to deposit the two fossilized
Oreohe/ix shells with Dr. Art Metcalf, who has amassed the largest collection of land snails in
the southwest. Upon returning to Albuquerque, the surveyors noticed large thunderhead
cloud formations congregating around the Florida Mountains, and made one last effort to
camp, awaiting the rains. On August 23, 1997, the surveyors returned home with no rain
events having occurred. No sites in the Tres Herrnanas Mountains were surveyed due to the
unfavorable weather conditions and apparent small amount of limestone habitat shown on the
geology maps.
It is the New Mexico Natural Heritage Program's opinion that Oreohelix florida is in fact
extinct in the Florida Mountains. The first survey site at Baldy Peak was not only surveyed in
ideal conditions, with enough moisture present to activate landsnai1s, but is the only site in the
Florida Mountains harboring enough mesic habitat to potentially support a relic population of
Oreohelix florida. A future survey at that mountain is not recommended.
Partnerships
The two fossilized shells were deposited in the Invertebrate Collection at the University of
Texas at El Paso with Dr. Art Metcalf, who confirmed their identification and added them to
the collection as specimen # 13,725. In addition, the rancher who has the public grazing
allotment for the Florida Mountains kindly gave us directions to the easiest access to them.
Next Steps
Additional surveys should be conducted during ideal conditions in potential habitat on the
other three mountains where fossil shells of Oreohelix florida exist before the global rank is
changed to extinct (OX).
Communications
Because this species has not been found alive, it is doubtful that this investigation would hold
much general public interest and media appeal. However, a media communication on the
numerous globally imperiled talus slope land snails that exist on small "sky island" mountains
as relicts of the more moist Pleistocene epoch could have substantial media appeal. We have
no video tape or art, other than drawings of this species, however, photographs were taken of
the Baldy Peak survey sites.

nmnhp.unm.edu/vlibrary/pubs_archive/nmnhp/nonsensitive/U97SCO03NMUS.pdf

[another specialist]

Comments

The common name was changed from Florida Mountains oreohelix to Florida Mountainsnail when it was listed Endangered (Group 1) on November, 30, 1990 *06*.

Comments on Status

1990: The Florida Mountainsnail was listed Endangered (Group 1) on November 30, 1990 (NMDGF, 1990)*06*. 1991: This species has been placed by the November 21, 1991 Federal Register, in Category 2 (Fed.Reg., 1991)*07*. 1994, Biologist's Recommendation: In spring 1994 NMDGF recommended to the State Game Commission that the legal status of the Florida mountainsnail (Oreohelix florida) remain "Group 1" (= Endangered) within New Mexico *12*(NMDGF, 1994). 1994: The Florida mountainsnail (Oreohelix florida) is listed in the Federal Register, November 15, 1994, as a Category 2 species for consideration to be listed as a threatened or endangered species (Fed.Reg., 1994)*09*. 1996: The USFWS has changed listing status of "Federal Candidate" species. This classification formerly included three subclassifications: Federal Candidate: Category 1, Category 2, and Category 3. There are no longer "Category" designations. This species was listed as a Federal Candidate Category 2 species. Species formerly designated Category 2 and 3 are NO LONGER CONSIDERED FEDERAL CANDIDATE SPECIES, and so no longer have any Federal protection under the "Candidate" listing. However, such species may retain other federal or state designated protections (Federal Reg., Feb. 28, 1996) *14*. 1996: The species, Oreohelix florida, was listed by a New Mexico Natural Heritage Program list as "Tracked": data were being actively accumulated and entered into computerized and manual files by the Heritage Program (NMNHP, 1996)*16*. 1996 (March): Former C2 species are now classified as Federal:"Species of Concern" (Jahrsdoerfer, 1996) *17*. NEW MEXICO 1996, Biologist's Recommendation: No change in the legal status of the species is recommended by the NMDGF at this time. However, field inventory is required to determine if this species is extinct and should be removed from the state list (NMDGF, 1996)*15*.

Comments on Trends

This species may be extinct, as it is known only from a few recent shells taken in the Florida Mountains. Based on the presence of fossil shells in several mountain ranges in addition to the Floridas, it is clear that this species once had a wider range in southwestern New Mexico (NMDGF, 1990)*06*. 1991: The specie's population trend is Unknown. Additional survey work is required to determine the species current trends (Fed.Reg., 1991)*07*. 1994: The trend of the species' population is listed "Unknown" (Fed. Register 1994)*09*. 1996: The presence of subfossil shells in several mountain ranges throughout southern New Mexico (Santa Rita and Tres Hermanas mountains and Cooke's Peak), imply significant reduction of the species historic range. The species may be extinct, as it is known only from recently dead shells; no live snails have been found (NMDGF, 1996)*15*.

Comments on Distribution

NEW MEXICO
1999: Species is considered extinct (AFA, 1999) *21*.

1997: The taxa has a very localized distribution and is found within the
following township(s): T 25, 26 S, R 8 W. Please contact the NM Department
of Game and Fish, Endangered Species Program, Santa Fe, NM if more specific
information is needed (Lang, 1997) *19*.

1994: The "Historic range" of the Florida mountainsnail (Oreohelix florida)
includes areas of New Mexico, but is not found beyond the state's borders
(Fed. Register 1994) *09*.

1990: The Florida woodlandsnail is endemic to the Florida Mts. of
southwestern New Mexico. This species was described from recent shells
collected near the central peak on the west side of the Florida Mts. Fossil
shells of this snail have also been reported in the Cooke's Range and Tres
Hermanas and Santa Rita Mts (NMDGF, 1990) *06*.

Comments on General Environmental Associations

In a study of terrestrial gastropods of central and north-central New Mexico (1952-54) it was found that the greatest number of species was fund in the 8100 to 9000-foot and 9100 to 10,000-foot encrements, with a slightly smaller number in the 7100 to 8000-foot increment. The numbers of different species found at various elevations decline strongly above 10,000 feet and are drastically reduced below 7500 feet *10*(Hoff, 1962).

Comments on Limiting Environmental Associations

Based on data available up to the early 1960's, it appears that most Gastropod species are infrequently found beyond the limits of a 3000-foot band of elevation and that snails are generally infrequent below 7000 feet *10*(Hoff, 1962).

Comments on Life History Codes

The Florida woodlandsnail is endemic to the Florida Mts. of southwestern New Mexico. This species was described from recent shells collected near the central peak on the west side of the Florida Mts. Fossil shells of this snail have also been reported in the Cooke's Range and Tres Hermanas and Santa Rita Mts *06*. The "Historic range" of the Florida mountainsnail (Oreohelix florida) includes areas of New Mexico, but is not found beyond the state's borders *09*(Fed. Register 1994).

Comments on Management Practices

Potential habitat for the Florida woodlandsnail should be protected in the Florida Mts, in case an overlooked population of the species still persists. This protection should include the exclusion of mining and other substrate-disturbing activities in limestones areas in the vicinity of Baldy Peak *06*.

Comments on Recommended Management Practices

1996, Biologist's Recommendation: Field inventory is required to determine if this species is extinct and should be removed from the NM state list (NMDGF, 1996)*15*.

Comments on Population Status

The Florida mountainsnail (Oreohelix florida) is listed in the Federal Register, November 15, 1994, as a Category 2 species for consideration to be listed as a threatened or endangered species. The trend of the species' population is listed "Unknown" *09*(Fed. Register 1994). 1996, Threats: Although threats are not easily identified, as an extant population has not yet been documented, potential threats include natural catastrophes (rock slide, forest fire) and soil disturbances associated with mining (NMDGF, 1996)*15*.

www.fw.vt.edu/fishex/nmex_main/species/060071.htm

[another specialist]

www.biodiversityassociates.org/wildspecies/news/springsnail_listing_petition.pdf

[another specialist]

Rounded Global Status: GX - Presumed Extinct
Reasons: No live individuals have been found with diligent survey efforts (Metcalf and Smartt, 1997; Score, 1997).

Global Abundance: AC
Global Abundance Comments: Seaching by Pilsbry turned up mostly fossils, but two old shells as well, suggesting numbers of live individuals are very reduced or non-existant.

Estimated Number of Element Occurrences: A
Estimated Number of Element Occurrences Comments: No live individuals have ever been found. It is known from fossil specimens at five disjuct sites: the Florida, Santa Rita and Tres Hermanos Mountains, the base of Cooke's Peak and the Apache Hills (Metcalf and Smartt, 1997). Pilsbry (1939) found two very old broken shells at the Florida Mountain locality, suggesting that site is most likely to support an extant population. However, in August 1997 under ideal survey conditions (high moisture immediately following heavy rains), no live individuals or non-fossilized shells were found (Score, 1997) at the same site.

Global Short Term Trend: AC
Global Short Term Trend Comments: Based on fossil evidence, the species appears to have gone extinct from five disjunct montane sites (Metcalf and Smartt, 1997).

Global Inventory Needs: Survey for live individuals. Based on two non-fossilized, but old shells, the Florida Mountains, Dona Anna County, New Mexico appear to be the most likely site for them.


Global Protection: B
Global Protection Comments: The species is State Endangered, which protects live individuals from collection without a permit. While that is the only formal protection afforded the species, the remoteness and poor accessibility of its habitat provide additional, passive protection.
Global Protection Needs: No additional protection actions are warrented unless the species is found to be extant.


Degree of Threat: D
Threats: Based on fossil evidence that the range has contracted, climate warming appears to be a major threat if not the cause of extinction of the species.


Fragility Comments: The species appears to have been sensitive to climate warming.

Other Considerations: Metcalf and Smartt (1997) consider the species to be extinct.

Global Range Comments: A regional endemic with fossil shells and old shells known from five mountain sites over a 1,000 sq. km. area. Fossil specimens have been found in the Florida, Santa Rita, and Tres Hermanos Mountains, at the base of Cooke's Peak, and in the Apache Hills in Dona Anna County, New Mexico (Metcalf and Smartt, 1997). No live individuals have ever been found.

www.natureserve.org/