Endangered and Threatened Wildlife and Plants; Listing Determinations for Five Poecilotheria Tarantula Species From Sri Lanka
Federal Register, Volume 81 Issue 240 (Wednesday, December 14, 2016)
Federal Register Volume 81, Number 240 (Wednesday, December 14, 2016)
Proposed Rules
Pages 90297-90314
From the Federal Register Online via the Government Publishing Office www.gpo.gov
FR Doc No: 2016-30059
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DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
Docket No. FWS-HQ-ES-2016-0076; 4500030115
RIN 1018-BB33
Endangered and Threatened Wildlife and Plants; Listing Determinations for Five Poecilotheria Tarantula Species From Sri Lanka
AGENCY: Fish and Wildlife Service, Interior.
ACTION: Proposed rule.
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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), announce a proposal to list the following five tarantula species under the Endangered Species Act of 1973, as amended (Act): Poecilotheria fasciata, P. ornata, P. smithi, P. subfusca, and P. vittata. This document also serves as the 12-month finding on a petition to list these species. After review of the best available scientific and commercial information, we find that listing each of these species is warranted and propose listing all of them as endangered species.
DATES: We will accept comments received or postmarked on or before February 13, 2017. Comments submitted electronically using the Federal eRulemaking Portal (see ADDRESSES below) must be received by 11:59 p.m. Eastern Time on the closing date. We must receive requests for public hearings, in writing, at the address shown in FOR FURTHER INFORMATION CONTACT by January 30, 2017.
ADDRESSES: You may submit comments by one of the following methods:
(1) Electronically: Go to the Federal eRulemaking Portal: http://www.regulations.gov. In the Search box,
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enter FWS-HQ-ES-2016-0076, which is the docket number for this rulemaking. Then, in the Search panel on the left side of the screen, under the Document Type heading, click on the Proposed Rules link to locate this document. You may submit a comment by clicking on ``Comment Now!''
(2) By hard copy: Submit by U.S. mail or hand-delivery to: Public Comments Processing, Attn: FWS-HQ-ES-2016-0076; U.S. Fish & Wildlife Service Headquarters, MS: BPHC, 5275 Leesburg Pike, Falls Church, VA 22041-3803. We request that you send comments only by the methods described above. We will post all comments on http://www.regulations.gov. This generally means that we will post any personal information you provide us (see Public Comments below for more information).
FOR FURTHER INFORMATION CONTACT: Janine Van Norman, Chief, Branch of Foreign Species, Ecological Services, U.S. Fish and Wildlife Service, MS: ES, 5275 Leesburg Pike, Falls Church, VA 22041-3803; telephone, 703-358-2171; facsimile, 703-358-1735. Persons who use a telecommunications device for the deaf (TDD) may call the Federal Information Relay Service (FIRS) at 800-877-8339.
SUPPLEMENTARY INFORMATION:
Executive Summary
Why we need to publish a rule. Under the Act, if a species is determined to be an endangered or threatened species throughout all or a significant portion of its range, we are required to promptly publish a proposal in the Federal Register and make a determination on our proposal within 1 year. Listing a species as an endangered or threatened species can only be completed by issuing a rule.
This document proposes the listing of the tarantula species Poecilotheria fasciata, P. ornata, P. smithi, P. subfusca, and P. vittata as endangered species. This proposed rule assesses the best available information regarding status of and threats to these named species.
The basis for our action. Under the Act, we can determine that a species is an endangered or threatened species based on any one or more of five factors or the cumulative effects thereof: (A) The present or threatened destruction, modification, or curtailment of its habitat or range; (B) Overutilization for commercial, recreational, scientific, or educational purposes; (C) Disease or predation; (D) The inadequacy of existing regulatory mechanisms; or (E) Other natural or manmade factors affecting its continued existence. We have determined that P. fasciata, P. ornata, P. smithi, P. subfusca, and P. vittata are in danger of extinction due to ongoing habitat loss and degradation and the cumulative effects of this and other threat factors. One species, P. smithi, is also in danger of extinction due to the effects of stochastic (random) processes.
We will seek peer review. We will seek comments from independent specialists to ensure that our designation is based on scientifically sound data, assumptions, and analyses. We will invite these peer reviewers to comment on our listing proposal. Because we will consider all comments and information received during the comment period, our final determinations may differ from this proposal.
Information Requested
Public Comments
Our intent, as required by the Act, is to use the best available scientific and commercial data as the foundation for all endangered and threatened species classification decisions. Further, we want any final rule resulting from this proposal to be as accurate and effective as possible. Therefore, we invite the range country, tribal and governmental agencies, the scientific community, industry, and other interested parties to submit comments regarding this Proposed Rule. Comments should be as specific as possible.
Before issuing a final rule to implement this proposed action, we will take into account all comments and any additional relevant information we receive. Such communications may lead to a final rule that differs from our proposal. For example, new information provided may lead to a threatened status instead of an endangered status for some or all of the species addressed in this proposed rule, or we may determine that one or more of these species do not warrant listing based on the best available information when we make our determination. All comments, including commenters' names and addresses, if provided to us, will become part of the administrative record. For each of the five species, we particularly seek comments concerning:
(1) The species' biology, ranges, and population trends, including:
(a) Biological or ecological requirements of the species, including habitat requirements for feeding, breeding, and sheltering;
(b) Genetics and taxonomy;
(c) Historical and current range including distribution patterns;
(d) Historical and current population levels, and current and projected trends; and
(e) Past and ongoing conservation measures for the species, its habitat or both.
(2) Factors that may affect the continued existence of the species, which may include habitat modification or destruction, overutilization, disease, predation, the inadequacy of existing regulatory mechanisms, or other natural or manmade factors.
(3) Biological, commercial trade, or other relevant data concerning any threats (or lack thereof) to the species and existing regulations that may be addressing those threats.
(4) Additional information concerning the historical and current status, range, distribution, and population size of the species, including the locations of any additional populations of the species.
Please include sufficient information with your submission (such as scientific journal articles or other publications) to allow us to verify any scientific or commercial information you include.
Please note that submissions merely stating support for or opposition to the action under consideration without providing supporting information, although noted, will not be considered in making a determination, as section 4(b)(1)(A) of the Act directs that determinations as to whether any species is a threatened or endangered species must be made ``solely on the basis of the best scientific and commercial data available.''
You may submit your comments and materials concerning this proposed rule by one of the methods listed in ADDRESSES. We request that you send comments only by the methods described in ADDRESSES.
If you submit information via http://www.regulations.gov, your entire submission--including any personal identifying information--will be posted on the Web site. If your submission is made via a hardcopy that includes personal identifying information, you may request at the top of your document that we withhold this information from public review. However, we cannot guarantee that we will be able to do so. We will post all hardcopy submissions on http://www.regulations.gov.
Comments and materials we receive, as well as supporting documentation we used in preparing this proposed rule, will be available for public inspection on http://www.regulations.gov, or by appointment, during normal business hours, at the U.S. Fish and Wildlife Service, Headquarters Office (see FOR FURTHER INFORMATION CONTACT).
Public Hearing
Section 4(b)(5) of the Act provides for one or more public hearings on this
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proposal, if requested. Requests must be received within 45 days after the date of publication of this proposed rule in the Federal Register. Such requests must be sent to the address shown in FOR FURTHER INFORMATION CONTACT. We will schedule public hearings on this proposal, if any are requested, and announce the dates, times, and places of those hearings, as well as how to obtain reasonable accommodations, in the Federal Register and local newspapers at least 15 days before the hearing.
Peer Review
In accordance with our joint policy on peer review published in the Federal Register on July 1, 1994 (59 FR 34270), we will solicit the expert opinion of at least three appropriate and independent specialists for peer review of this proposed rule. The purpose of peer review is to ensure that our listing determinations are based on scientifically sound data, assumptions, and analyses. We will send peer reviewers copies of this proposed rule immediately following publication in the Federal Register. We will invite peer reviewers to comment, during the public comment period, on the specific assumptions and conclusions regarding the proposed listing status of each of the five tarantula species. We will summarize the opinions of these reviewers in the final decision document, and we will consider their input and any additional information we receive, as part of our process of making a final decision on the proposal.
Previous Federal Action
We received a petition, dated October 29, 2010, from WildEarth Guardians requesting that the following 11 tarantula species in the genus Poecilotheria be listed under the Act as endangered or threatened: Poecilotheria fasciata, P. formosa, P. hanumavilasumica, P. metallica, P. miranda, P. ornata, P. pederseni, P. rufilata, P. smithi, P. striata, and P. subfusca. The petition identified itself as such and included the information as required by 50 CFR 424.14(a). We published a 90-day finding on December 3, 2013 (78 FR 72622), indicating that the petition presents substantial scientific and commercial information indicating that listing these 11 species may be warranted. At that time we also (1) notified the public that we were initiating a review of the status of these species to determine if listing them is warranted, (2) requested from the public scientific and commercial data and other information regarding the species, and (3) notified the public that at the conclusion of our review of the status of these species, we would issue a 12-month finding on the petition, as provided in section 4(b)(3)(B) of the Act. This document represents our review and determinations of the status of the five petitioned species that are endemic to Sri Lanka (Poecilotheria fasciata, P. ornata, P. pederseni, P. smithi, and P. subfusca), our publication of our 12-month finding on these five species, and our proposed rule to list these species. We will issue our determinations on other tarantula species in the genus Poecilotheria separately after we complete our review.
Background
Taxonomy and Species Descriptions
Poecilotheria is a genus of arboreal spiders endemic to Sri Lanka and India. The genus belongs to the family Theraphosidae, often referred to as tarantulas, within the infraorder Mygalomorphae (Table 1). As with most theraphosid genera, Poecilotheria is a poorly understood genus. The taxonomy has never been studied using modern DNA technology; therefore, species descriptions are based solely on morphological characteristics. Consequently, there have been several revisions, additions, and subtractions to the list of Poecilotheria species over the last 20 years (Nanayakkara 2014a, pp. 71-72; Gabriel and Gallon 2013, entire).
The World Spider Catalog (2016, unpaginated) currently recognizes 14 species of Poecilotheria. The Integrated Taxonomic Information System currently identifies 16 species in the genus, based on the 2011 version of the same catalog. Because the World Spider Catalog is the widely accepted authority on spider taxonomy, we consider the Poecilotheria species recognized by the most recent (2016) version of this catalog to be valid. Based on the World Spider Catalog, all five of the petitioned species are considered valid taxon, though P. pederseni is now considered a junior synonym to the currently accepted name P. vittata (Table 1). Therefore, in the remainder of this document we refer to this species as P. vittata. Further, all five of these species have multiple common names (see WildEarth Guardians 2010, p. 4) and are, therefore, referred to by their scientific names throughout this document.
Table 1--Scientific Classification of Five Sri Lankan Poecilotheria
Species Petitioned for Listing as Endangered or Threatened Under the Act
See 78 FR 72662, December 3, 2013
Synonyms are in parentheses
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Scientific Classification
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KINGDOM................................... Animalia.
PHYLUM................................... Arthropoda.
SUBPHYLUM................................ Chelicerata.
CLASS.................................... Arachnida.
ORDER.................................... Araneae.
INFRAORDER............................... Mygalomorphae.
FAMILY................................... Theraphosidae.
GENUS.................................... Poecilotheria.
SPECIES.................................. P. fasciata, P. ornata, P.
smithi (P. pococki), P.
subfusca (P. bara, P.
uniformis), P. vittata (P.
pederseni).
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Poecilotheria species are among the largest spiders in the world, with body lengths of 4 to 9 centimeters (1.5 to 3.5 inches) and maximum adult leg spans varying from 15 to 25 centimeters (6 to 10 inches) (Nanayakkara 2014a, pp. 94-129; Molur et al. 2006, p. 23). They are known for their very fast movements and potent venom that, in humans, typically causes extended muscle cramps and severe pain (Fuchs 2014, p. 75; Nanayakkara and Adikaram 2013, p. 53). They are hairy spiders and have striking coloration, with dorsal color patterns of gray, black, brown, and in one case, a metallic blue. Ventral coloration of either sex is typically more of the same with the exception of the first pair of legs, which often bear bright yellow to orange aposematic (warning) markings that are visible when the spider presents a defensive display. Mature spiders exhibit some sexual dimorphism with mature males having a more drab coloration and being significantly smaller than the adult females (Nanayakkara 2014a, entire; Pocock 1899, pp. 84-86).
The primary characteristics used to distinguish Poecilotheria species are ventral leg markings (Gabriel 2010 p. 13, citing several authors). Some authors indicate that identification via leg markings is straightforward for most Poecilotheria species (Nanayakkara 2014a, pp. 74-75; Gabriel 2011a, p. 25). However, the apparent consistent leg patterns observed in adults of a species could also be a function of specimens being collected from a limited number of locations (Morra 2013, p. 129). During field surveys, researchers found more variation than suggested by published
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species descriptions and indicated that identifying Poecilotheria species is not as straightforward as suggested by current descriptions (Molur et al. 2003, unpaginated). Reports of inadvertent production of hybrids within the tarantula trade (see Gabriel 2011a, p. 26) also indicate a degree of difficulty in identification of adult specimens. Immature spiders (juveniles) lack the variation in coloring found in adults. As a result, they are difficult to differentiate visually; genetic analysis may be the only way to reliably identify juveniles to species (Longhorn 2014a, unpaginated).
Captive Poecilotheria
Poecilotheria species are commonly bred in captivity by amateur hobbyists as well as vendors, and are available as captive-bred young in the pet trade in the United States, Europe, and elsewhere (see Trade). However, while rearing and keeping of captive individuals by hobbyists and vendors has provided information on life history of these species, these captive individuals hold limited conservation value to the species in the wild. Individuals in the pet trade descend from wild individuals from unknown locations, have undocumented lineages, come from limited stock (e.g., see Gabriel 2012, p. 18) and are bred without knowledge or consideration of their genetics. They also likely include an unknown number of hybrid individuals resulting from intentional crosses, or unintentional crosses resulting from confusion and difficulty in species taxonomy and identification (Gabriel 2011a, pp. 25-26; Gabriel et al. 2005, p. 4; Gabriel 2003, pp. 89-90). Further, many are likely several generations removed from wild ancestors and thus may be inbred or maladapted to conditions in the wild. In short, captive individuals held or sold as pets do not adhere to the IUCN guidelines for reintroductions and other conservation translocations (IUCN 2013, entire). Further, we are not aware of any captive-breeding programs for Poecilotheria that adhere to IUCN guidelines. Because (1) the purpose of our status assessments is to determine the status of the species in the wild, and (2) captive individuals in the hobby or pet trade have low value for conservation programs or for reintroduction purposes, we place little weight on the status of captive individuals in our assessment of the status of the five petitioned Poecilotheria species endemic to Sri Lanka.
Tarantula General Biology
Tarantulas possess life-history traits markedly different from most spiders and other arthropods (Bond et al. 2006, p. 145). They are long-
lived, have delayed sexual maturity, and most are habitat specialists that are extremely sedentary. They also have poor dispersal ability because their mode of travel is limited to walking, and they typically do not move far from the area in which they are born. As a result, the distribution of individuals tends to be highly clumped in suitable microhabitats (a smaller habitat within a larger habitat), populations are extremely genetically structured, and the group shows a high level of endemism (species restricted to a particular geographical location) (Ferreti et al. 2014, p. 2; Hedin et al. 2012, p. 509, citing several sources; Bond et al. 2006, pp. 145-146, citing several sources).
Tarantulas are primarily nocturnal and typically lead a hidden life, spending much of their time concealed inside burrows or crevices (retreats) that provide protection from predators and the elements (Foelix 2011, p. 14; Molur et al. 2003, unpaginated; Gallon 2000, unpaginated). They are very sensitive to vibrations and climatic conditions, and usually don't come out of their retreats in conditions like rains, wind, movement, or excessive light (Molur et al. 2003, unpaginated). Tarantulas are generalist predators that sit and wait for passing prey near the entrance of their retreats (Gallon 2000, unpaginated). With the exception of reproductive males that wander in search of females during the breeding season, they leave their retreat only briefly for capturing prey, and quickly return to it at the slightest vibration or disturbance (Foelix 2011, p. 14; Stotley and Shillington 2009, pp. 1210-1211; Molur et al. 2003, unpaginated). Tarantulas generally inhabit a suitable retreat for extended periods and may use the same retreat for years (Stotley and Shilling 2009, pp. 1210-1211; Stradling 1994, p. 87). Most tarantulas are solitary, with one spider occupying a retreat (Gallon 2000, unpaginated).
The lifestyle of adult male tarantulas differs from that of adult females and juveniles. Females and juveniles are sedentary, spending most of their time in or near their retreat. Adult females are also long-lived, and continue to grow, molt, and reproduce for several years after reaching maturity (Ferreti et al. 2014, p. 2, citing several sources; Costa and Perez-Miles 2002, p. 585, citing several sources; Gallon 2000, unpaginated). They are capable of producing one brood per year although they do not always do so (Ferreti et al. 2014, p. 2; Stradling 1994, pp. 92-96). Males have shorter lifespans than females and, after reaching maturity, no longer molt and usually only live one or two breeding seasons (Costa and Perez-Miles 2002, p. 585, Gallon 2000, unpaginated). Further, on reaching maturity, males leave their retreats to wander in search of receptive females with which to mate (Stotley and Shillington 2009, pp. 1210-1211). Males appear to search the landscape for females randomly and, at short range, may be able to detect females through contact sex-pheromones on silk deposited by the female at the entrance of her retreat (Ferreti et al. 2013, pp. 88, 90; Janowski-Bell and Hommer 1999, pp. 506, 509; Yanez et al. 1999, pp. 165-167; Stradling 1994, p. 96). Males may cover relatively large areas when searching for females. Males of a ground-dwelling temperate species (Aphonopelma anax) are reported covering search areas up to 29 ha (72 acres), though the mean size of areas searched is much smaller (1.1 0.5 ha one year and 8.8 2.5 ha another year) (Stotley and Shillington 2009, p. 1216).
When a male locates a receptive female, the two will mate in or near the entrance to the female's retreat. After mating, the female returns to her retreat where she eventually lays eggs within an egg-sac and tends the eggs until they hatch. Spiderlings reach maturity in one or more years (Gallon 2000, unpaginated).
Poecilotheria Biology
Limited information is available on Poecilotheria species in the wild. However, they appear to be typical tarantulas in many respects. However, they differ from most tarantulas in that they are somewhat social (discussed below) and reside in trees rather than ground burrows (see Microhabitat).
Poecilotheria species are patchily distributed (Siliwal et al. 2008, p. 8) and prey on a variety of insects, including winged termites, beetles, grasshoppers, and moths, and occasionally small vertebrates (Das et al. 2012, entire; Molur et al. 2006, p. 31; Smith et al. 2001, p. 57).
We are not aware of any information regarding the reproductive success of wild Poecilotheria species. However, reproduction may be greatly reduced during droughts (Smith et al. 2001, pp. 46, 49). Additionally, given the apparently random searching for females by male tarantulas, successful mating of females likely depends on the density of males in the vicinity. In the only field study conducted on an
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arboreal tropical tarantula (Avicularia avicularia in Trinidad), less than half of adult females produced eggs in the same year despite the fact that they were in close proximity to each other and exhibited the same weight gain, possibly due to a failure to mate (Stradling 1994, p. 96).
Time to maturity in Poecilotheria species varies and is influenced by the temperature at which the young are raised and amount of food provided (Gabriel 2006, entire). Based on observations of captive Poecilotheria, males mature from spiderlings to adults in 11 to16 months (Gabriel 2011b, P. 101; Gabriel 2005, entire). Females can mature within 14 months and generally live an additional 60 to 85 months after maturing (Gabriel 2012, p. 19; Government of Sri Lanka and Government of the United States 2000, p. 3), although they have been reported living up to 14 years (Gallon 2012, p. 69). Females lay about 50 to 100 eggs, 5 to 6 months after mating (Nanayakarra 2014a, p. 79; Gabriel 2011b, entire; Gabriel 2005, p. 101). In captivity, generation time appears to be roughly 2-3 years (see Gabriel 2011b, entire; Gabriel 2006, p. 96; Gabriel 2005, entire). While captive individuals provide some indication of potential growth, longevity, and reproductive capacity of wild individuals, these variables are likely to vary with conditions in the wild. Poecilotheria are ectotherms and, as such, their physiological and developmental processes including growth and reproduction are strongly influenced by body temperature and it is likely that captive-rearing of these species is primarily done under ideal environmental conditions for reproduction and growth.
Unlike most tarantulas, which are solitary, most Poecilotheria species display a degree of sociality. Adult females often share their retreat with their spiderlings. Eventually as the young mature, they disperse to find denning areas of their own. Occasionally young remain on their natal tree to breed, or three to four adult females will share the same retreat (Nanayakkara 2014a, pp. 74, 80). These semi-social behaviors are believed to be a response to a lack of availability of suitable habitat (trees) in which individuals can reside (Nanayakkara 2014a, pp. 74, 80; Gallon 2000, unpaginated).
Poecilotheria Habitat
Microhabitat
Poecilotheria occupy preexisting holes or crevices in trees or behind loose tree bark (Molur et al. 2006, p. 31; Samarawckrama et al. 2005; Molur et al. 2003 unpaginated; Kirk 1996, pp. 22-23). Individuals of some species are also occasionally found in grooves or crevices in or on other substrates such as rocks or buildings that are close to wooded areas (Samarawckrama et al. 2005, pp. 76, 83; Molur et al. 2003, unpaginated). In a survey in Sri Lanka, 89 percent (31) of Poecilotheria spiders were found in or on trees, while 11 percent (4) were found in or on buildings (Samarawckrama et al. 2005, p. 76). Poecilotheria species are said to have a preference for residing in old, established trees with naturally occurring burrows (Nanayakkara 2014a, p. 86). Some species also appear to prefer particular tree species (Nanayakkara 2014a, p. 84; Samarawckrama et al. 2005, p. 76).
Macrohabitat
Most Poecilotheria species occur in forested areas, although some occasionally occur in other treed habitats such as plantations (Nanayakkara 2014a, p. 86; Molur et al. 2006, p. 10; Molur et al 2003, entire; Smith et al. 2001, entire). Poecilotheria are less abundant in degraded forest (Molur et al. 2004, p. 1665). Less complex, degraded forests may contain fewer trees that provide adequate retreats for these species and less cover for protection from predators and the elements. Trees with broad, dense canopy cover likely provide Poecilotheria in hotter, dryer habitats protection from heat and desiccation (Siliwal 2008, pp. 12, 15). We provide additional, species-
specific information on habitat below.
Sri Lanka
Sri Lanka is an island nation about 65,610 square kilometers (km\2\) (25,332 square miles (mi\2\)) in area (Weerakoon 2012, p. xvii), or about the size of West Virginia (Fig. 1). The variation in topography, soils, and rainfall on the island has resulted in a diversity of ecosystems with high levels of species endemism (Government of Sri Lanka (GOSL) 2014, pp. xiv-xv). Sri Lanka, together with the Western Ghats of India, is identified as a global biodiversity hotspot, and is among the eight ``hottest hotspots,'' (Myers et al. 2000, entire).
Sri Lanka consists of a mountainous region (central highlands), reaching 2,500 m in elevation, in the south-central part of the island surrounded by broad lowland plains (GOSL 2012, p. 2a-3-141) (Fig. 2). The country has a tropical climate characterized by two major monsoon periods: The southwest monsoon from May to September and the northeast monsoon from December to February (GOSL 2012, pp. 7-8).
Sri Lanka's central highlands create a rain shadow effect that gives rise to two pronounced climate zones--the wet zone and dry zone--
and a less extensive intermediate zone between the two (Ministry of Environment--Sri Lanka (MOE) 2010, pp. 21-22) (Fig. 2). Small arid zones also occur on the northwestern and southeastern ends of the country (Nanayakkara 2014a, p. 22). Annual rainfall ranges from less than 1,000 millimeters (mm) (39.4 inches (in)) in the arid zone to over 5,000 mm (197 in) in the central highlands (Jayatillake et al. 2005, pp. 66-67). Mean annual temperature ranges from 27 degrees Celsius (degC) (80.6 degrees Fahrenheit (degF)) in the lowlands to 15 degC (59emsp14degF) in the highlands (Eriyagama et al. 2010, p. 2).
The wet zone is located in the southwestern quarter of the island, where high annual rainfall is maintained throughout the year by rain received during both monsoons and during inter-monsoonal periods (MOE 2010, pp. 21-22) (Fig. 2). The wet zone is divided into low, mid, and montane regions based on altitude (Table 2). The dry zone, in which most of the land area of Sri Lanka occurs, is spread over much of the lowland plains and is subjected to several months of drought (MOE 2010, pp. 21-22) (Table 2) (Fig. 2). Most of the rain in this zone comes from the northeast monsoon and inter-monsoonal rains (MOE 2010, pp. 21-22; Malgrem 2003, p. 1236). Characteristic forest types occur within each of the different climate zones (Table 2).
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Table 2--Climate Zones and Elevation of Sri Lanka and Associated Forest Types
Based on Information in FAO (2015a, pp. 6-7), Nanayakkara (2014a, pp. 22-25), and GOSL (2012, p. 51)
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Percent of
Zone Sri Lanka's Mean annual Elevation Forest type
land area rainfall (mm) (meters)
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Wet Zone.............................. 23 2,500->5,000 0-2,500 ........................
Low............................... .............. .............. 0-1,000 Lowland rainforest.
Mid............................... .............. .............. 1,000-1,500 Submontane forest.
Montane........................... .............. .............. 1,500-2,500 Montane forest.
Intermediate Zone..................... 12 1,900-2,500 0-1,000 Moist monsoon forest.
Dry Zone.............................. 60 1,250-1,900 0-500 Dry monsoon forest;
riverine forest; open-
canopy forest.
Arid Zone............................. 5
