Fire Dependent Belize: an Investigation of Lowland Savanna Ecology and Pine Regeneration

Fire Dependent Belize: An Investigation of Lowland Savanna Ecology and Pine Regeneration

Kenny Duffield ⁕ [email protected] School of Forest Resources & Conservation Advisor: Dr. Michael Andreu CALS Honors Program

Contents 1. Abstract………………………………………………………………………………………..3 2. Acknowledgments……………………………………………………………………………..4 3. Introduction……………………………………………………………………………………5 3.1. Goals of Research………………………………………………………………………...6 3.2. Study Area………………………………………………………………………………..6 3.3. Site History……………………………………………………………………………….7 4. Background…………………………………………………………………………………..10 4.1. Lowland Pine Savannas…………………………………………………………………10 4.2. Fire in Tropical Pine Ecosystems……………………………………………………….11 4.3. Current Issues: Too Much Fire………………………………………………………….13 4.4. Conservation Status: Lowland Pine Savannas…………………………………………..14 4.5. Conservation Status: Amazona oratrix belizensis……………………………………….15 5. Methods………………………………………………………………………………………16 5.1. Cover Composition……………………………………………………………………...16 5.2. Species Richness………………………………………………………………………..19 5.3. Pine Data & Mapping………..………………………………………………………….20 5.4. Four Meter Transects……………………………………………………………………21 5.5. Vertical Obstruction……………………………………………………………………..21 5.6. Radial Plots……………………………………………………………………………...23 6. Results………………………………………………………………………………………..23 6.1. Cover Composition……………………………………………………………………...23 6.2. Species Richness……………………………………………………………………...…24 6.3. Pine Data & Mapping…………………………………………………………………...25 6.4. Four Meter Transects……………………………………………………………………26 6.5. Vertical Obstruction…………………………………………………………………….26 6.6. Radial Plots……………………………………………………………………………...27 6.7. Snags………………………………………………………………………………….…27 7. Conclusion…………………………………………………………………………………...28 8. Further Research………………………………………………………………………...…...30 9. Work Cited…………………………………………………………………………………...31

Abstract

Today in Belize, lowland pine savannas occupy roughly 148,000 ha, an area that has reduced by 20,000 ha since 1980. Belize’s lowland savannas are the most northerly example of lowland savannas in the Americas and have been the subject of very few studies. As a result, many of the savannas throughout Belize are still unexplored botanically as are their environmental and economic services which include carbon sequestration, wildlife habitat and drainage. The understory of these savannahs are characterized by graminoids and a multitude of forb species with a low density of Pinus caribaea dominating the over story. In drought prone pine systems containing mixed graminoid and forb layers, fire regimes are a powerful influence of survival and a necessity for fuel reduction and pine regeneration. Today in Belize, many ecosystems are experiencing too much fire largely due to escaped human fires and wildfires that are exasperated by dryer and warmer seasons. These escaped fires are occurring with alarming frequency and lend to the destruction of local resources and biodiversity including the pine savanna habitats. As well, frequent fires may have allowed for grass and sedge domination within the understory, potentially enabling the abundance of one species at the cost of many more. Currently, detailed plant inventories and pine tree demographics are limited within these communities. After six weeks of data collection in both the understory and overstory, 58 separate species of grass, sedge, forb and woody plants, including Pinus caribae were documented. Through incredible collaboration and dedication, this study has contributed baseline data to the scientific community that can be employed to further fire ecology research within these systems.

Acknowledgments

I would like to first thank the incredible efforts of Sharon Matola and Celso Poot at the Belize zoo for facilitating this collaborative research and encouraging environmental excellence. Without their continued support, this project would have been nothing more than an idea. Betsy Mallory played a pivotal role in providing literature for plant identification and I cannot thank her enough for her expertise. I would also like to sincerely thank Dr. Michael Andreu, whose guidance, encouragement and example enabled me to reach new potential. My parents, Jill and Ken, also deserve the upmost appreciation for their endless encouragement. Finally, I would like to thank Dan Mills and Richard Foster. These individuals gave much of their own time so that this project could grow.

Introduction

Belize, formerly known as British Honduras, gained its independence from the United

Kingdom in 1981 following long territorial disputes between the UK and Guatemala. Belize has a total population of 353,858 and shares a border with Mexico to the north and Guatemala to the

South and West. Belize is located on the Yucatan Peninsula and occupies an area of 22,966 km2, just slightly smaller than the state of Massachusetts. The country can be divided into two major topographical regions: The Northern Lowlands and the Mountain Pine Ridge/ Maya Mountains to the south. The Northern lowlands were gradually raised from the ocean during the Pliocene

(5.3-2.6 million years BP) and are characterized by nutrient poor soils, often coarse textured at the surface (Acrisols) and frequently with poor seasonal drainage due to high clay contents. The

Mountain Pine Ridge and Maya Mountains rise to 1,124 meters above sea level and consist of shales, quartzite and granite intrusions that date from the Carboniferous and Permian period

(250-300 million years BP).1

The country hosts a subtropical/tropical climate with precipitation ranging from 1,200 mm (48”) in the north to 4,000mm (160”) in the south. This wide range in topography and precipitation creates a unique environment for a multitude of vegetative niches. In 2001, the

Central America Ecosystems Mapping Project identified eighty-five terrestrial ecosystems.

Currently, 69% of Belize is covered in some form of forest or shrubland with 50% occupied by broadleaf forest, 10% occupied by montane broadleaf and 9% occupied by lowland and pine savanna.2

1 Meerman, J C, and W Sabido. “Central American Ecosystems Map: Belize Volume 1.” (2001): Web

2 Ibid.

Goals of Research

Currently in Belize, there is a large gap in information concerning lowland pine savannas and specifically their responses to fire. There are large gaps in knowledge concerning, fire frequency, intensity, seasonality and fuel loads. It is the intention of this study to collect base line vegetative data to carry out long term fire research that may shed light on pine and understory regeneration. Before the completion of this study, vegetative density, richness and disbursement was unknown at this 22-acre site as well as demographic information on the 145 living pines.

Now that preliminary data has been collected, prescribed fire can be introduced in future studies so that vegetative resprouting and pine regeneration may be observed.

Study Area

The research took place on a lowland pine savanna located 1.5 km northeast of the Belize

Zoo at 17⁰21’41.7” N 88⁰32’46.7W. The 22-acre study area is part of the larger 1,700-acre savanna stewarded by the Belize Zoo. The property is in the Belize political district in North

Central Belize (Figure 1). A 22-acre plot was selected for this study consisting of 15 adjacently placed blocks each roughly 0.6 hectares. The total area of this study is 90,852 m2.

Figure 1. Belize zoo in red situated 31 km north of Belmopan and the Hummingbird Hgwy.

Site History

The mid 1980’s marked a shift in conservation land holdings in Belize. With mounting pressures from groups such as New York Zoological Society, Nature conservancy, World

Wildlife Fund and the Belize Audubon Society, large land holding companies like Bowen &

Bowen and Coca Cola Foods began divesting themselves from large tracts of land to avoid controversy over deforestation and development plans. Bowen & Bowen parted with 260,000 acres in Orange Walk that would later become Belize’s Rio Bravo Conservation and

Management Area, the largest nature reserve in Belize. One of Coca Cola’s divestments resulted in the transfer of 1,700 acres of pine savanna to the Belize Zoo. The property is now considered a

Land Trust and is officially listed as an Area of Conservation Concern, stewarded by the Belize

Zoo. The 1,700 acre property is adjacent to a privately managed 945 acre property currently owned by Pine Ridge Enterprise. These two properties joined would create 2,800 acres of protected land directly in the path of the Central Belize Corridor.

In the early 1970’s, Richard and Carol Foster, owner and operators of the Savanna Guest

House, made their permanent home in Central Belize. Richard recalled that when he first arrived,

“there was hardly a pine tree bigger than four inches.” Richard, having resided here for over 40 years with Carol, recalls that, “over the years no one has been allowed to cut pine trees.”

However, that wasn’t always the case as when Belize Estates, former British Colonial Company owned the land. “The Belize estates company…went through this area and completely clear cut it. They took every single big tree out of it. I suspect that this place, before man really had his foot print here, was a pretty big pine forest.” Richard then recalls, “When I first came, giant stumps. I mean the darn things were this far across” (Richard gestures about .5 meters in diameter with his hands) (Figure 2). “…And then someone in the late seventies came in with a big machine and pulled them all out. They shipped them out to the states because they were full of terpene.”3 Since then, the savanna has been without disturbance, slowly regenerating with pines and sparsely mixed hardwoods. The Belize Zoo’s ongoing efforts to promote education and research have made it possible to conduct studies here.

3 Foster, R. (2017, June 26). Personal interview

Figure 2. Remains of a pine species left after extensive logging of the area. Measurement with a DBH tape revealed a DBH of 45.6 cm. Water bottle for comparison is 12.06 cm wide.

Background

Lowland Pine Savannas

In 1993, topographic mapping revealed an original area of 168,000 ha of savannah throughout northern and southern Belize. They are the most northerly example of lowland savannas in the Americas and have been the subject of very few studies4. As a result, many of the savannas throughout Belize are still botanically unexplored as are their environmental and economic services which include wildlife habitat and drainage. These savannahs are characterized by a graminoid herbaceous layer dominated by sedges and herbaceous plants such as Cassytha filiformis, Diodela apiculate and the endemic Passiflora urbania. Other common shrubs and trees include Brysonima crassifolia, Gymnopodium floribundum, Bonelia macrocarpa and Cameraria latifoloa. Pinus caribaea dominates the over story but is sparse over the landscape.5 The soils consist of a thin surficial organic horizon over a densely packed layer of clay resulting in poor drainage during the rainy season (June-November). Deep ravines, carved into the clay by summer rains, were also observed during the study (Figure 3). These deep carvings in the landscape show evidence of discharging considerable amounts of water during the rainy season. This environment is also a critical habitat for Amazona oratrix belizensis which is listed as endangered by the International Union for Conservation of Nature. Amazona oratrix belizensis, a subspecies of Yellow-Headed parrot, is endemic to Belize and creates nesting cavities within mature living pines. Today in Belize, climate change and anthropogenic

4 Bridgewater, Sam, Iain Cameron, and Peter Furley. "Results of Darwin Initiative Project 17-022 and Implications for Savanna Conservation. Belize Tropical Forest Studies (BTFS), June 2012. Web. 5 Meerman, J. C., and W. Sabido. "Central American Ecosystems Map: Belize Volume II." (2001): Web.

10 influences are shaping the future of lowland savannas and without proper research, the importance of these habitats may be lost.

Figure 3: Heavy summer rains have been carved deep drainages on the savanna landscape.

Fire in tropical Pine Ecosystems

Tropical pine communities are systems often characterized by stress and disturbance. In drought prone pine systems containing a mixed graminoid herbaceous layer, fire regimes are a powerful influence and a necessity for fuel reductions and pine regeneration. 6 Understory

6 Myers, R.L (2006) Living with Fire: Sustaining Ecosystems and Livelihoods through Integrated Fire Management. The Nature Conservancy, Global Fire Initiative, Arlington, VA

11 grasses, sedges and forbs have maximized their utility within savannas by developing hardy root stock that readily resprout following fire. 7 Over time, pines have adapted with fire by developing fire tolerant seedlings stages, thick flaky bark, intermediate needle flushes, and natural pruning that prevents limb fires. Pinus caribaea has evolved with many of these adaptations and has relied on seasonal burns to promote its survival over competing species. 8 Fires within lowland pine savannas must be frequent enough to expose bare mineral soil and create canopy gap openings to allow for seedling establishment. However, if fires are too frequent, seedlings will be unable to reach a fire tolerant stage and may become outcompeted.

Many pine forest systems in Mesoamerica have undergone transformations due to logging, agriculture and development which has altered the structure and composition of the pine over-story. Historic undisturbed sites that received recurrent, low intensity surface fires have an uneven aged vertical structure. Larger DBH trees are generally spread throughout the forest while younger trees occur in patches that result from gap openings. This forest structure reflects a reverse “J” curve consisting of a higher number low DBH trees per acre. Gap openings are a critical part of these forests as successful seedling establishments tend to occur in these openings.9 Often these openings can occur from lightning strike or wind throw that occurs during tropical storms and hurricanes. Evidence of Southern Bark beetles (Dendroctonus frontalis) suggests that these insects may also take advantage of weakened trees furthering the opportunity for gap openings.

7 Brown, K.K. (2000) Introduction and fire regimes. Wildland fires in Ecosystems: Effect of fire on Flora, General Technical report RMRS-GTR-42-Vol-2. USDA Forest Service, Intermountain, Forest and Range Experiment Station, Ogden, UT. 8 Myer, Ronald L., and Dante Arturo Rodriguez-Trejo. Fire in Tropical Ecosystems. N.P.: Print. 9 Brown, K.K. (2000) Introduction and fire regimes. Wildland fires in Ecosystems: Effect of fire on Flora, General Technical report RMRS-GTR-42-Vol-2. USDA Forest Service, Intermountain, Forest and Range Experiment Station, Ogden, UT.

Current Issues: Too Much Fire

Today in Belize, many ecosystems are experiencing too much fire largely due to escaped human fires and wildfires that are exasperated by dryer and warmer seasons. Many human created fires quickly escape their intended confines spreading through human and natural communities alike. Human caused fires stem from a multitude of sources including slash and burn milpa, hunters, trash fires and even power companies in an attempt to de-brush power line roads. These escaped fires are occurring with alarming frequency and lend to the destruction of local resources and biodiversity including the pine savanna habitats.

Wildfires and the frequent fire return interval they promote has inhibited pine regeneration in open savannas. As quickly as seedlings are established, they are burned up leaving the ecosystem without a sustainable population of regenerating pine. However, organizations within the country such as the, Toledo Institute for Development and Environment

(TIDE), are creating programs to educate Belizeans about prescribed fire. TIDE, in coordination with the Belize Forest Department, Ya’axche Conservation Trust and two private logging concessionaires, have been fighting wildfires and conducting prescribed burns to mitigate intense fires that occur with increased fuel loads.10 TIDE is also investing in the community with annual prescribed fire courses that place the latest tools and techniques into the hands of local Belizeans.

Current estimations of Belizean savanna cover are based on combined efforts from the

Darwin Savanna Ecosystem Map 2010, and Landsat imagery originating from 1980. Analysis of these maps reveals that of the original 168,000 ha of savanna, 20,000 ha has already been

10 Fire Management | Toledo Institute for Development and Environment. TIDE, 2015. Web.

13 converted out of its natural savanna state to industrial use11. Most of these conversions are agricultural activities which include the manufacturing of pasture land in the Orange walk and

Cayo districts and shrimp farming aquiculture in Stan Creek and Toledo districts. Together, these industries represent 80% of the conversions of savanna habitat to agriculture. Since 2004, the aquiculture industry has generated BZ$ 84.28 million in revenue. With agriculture representing

11.7% of gross GDP, aquiculture represents just over 4% of the Belizean economy.12 Savannah ecosystems in Belize are also chosen for governmental infrastructure projects such as airstrips, housing and landfills. Phillip Goldson airport in Ladyville is located on a natural savanna as is the Plascencia airport, the capital city of Belmopan and its neighboring town of Mahogany

Heights.13

Conservation Status: Lowland Pine Savanna

Today in Belize, between 22-27% of lowland savannas remain undisturbed within protected areas. In Northern Belize, the largest protected tracts reside within the Rio Bravo

Conservation & Management Area and the Crooked Tree Wildlife Sanctuary. Many central

Belize savannas are privately protected in smaller patches such as in Runaway Creek, Monkey

Bay Wildlife Sanctuary and within the Tropical Education Center and Belize Zoo.14 Though the

Belize government has sanctioned many important reserves, many of the most efficiently operated areas are privately owned entities and Trusts which maintain funding through philanthropic means and educational programs. A ranking system developed by Roy Young

11 Bridgewater, Sam, Iain Cameron, and Peter Furley. "Results of Darwin Initiative Project 17-022 and Implications for Savanna Conservation. Belize Tropical Forest Studies (BTFS), June 2012. Web. 12 The World Factbook: BELIZE. Central Intelligence Agency. Central Intelligence Agency, 26 June 2017. Web. 13 Bridgewater, Sam, Iain Cameron, and Peter Furley. "Results of Darwin Initiative Project 17-022 and Implications for Savanna Conservation. Belize Tropical Forest Studies (BTFS), June 2012. Web. 14 Ibid.

(2005) for the National Protected Areas System Plan ranked the effectiveness of protected areas in Belize. The ranking was justified by many criteria including support services, biodiversity, monitoring, site management and financial sustainability. The results showed that privately owned management lands were more effectively managed than their counterparts within the government operated sector.

Conservation Status: Amazona oratrix belizensis

Amazona oratrix belizensis is a subspecies of yellow-head parrot that is endemic to

Belize and was officially listed as a CITES endangered species in 1994. A population estimate conducted in 1994 recorded a 90% population decrease from 70,000 to 7,000 over a duration of just two decades. Current estimates by Bird-life International place the population around 1,500 within a distribution range of 4,500 km2 15. The ability of these birds to replicate speech has made them a highly desirable item for the illegal pet trade which has substantially driven down their numbers. Poachers find it easy to spot their nests in pine trees and chop an access hole just below the nesting cavity to extract the fledglings. These poaching activities in combination with this species’ low fecundity, create a dire future for Amazona Oratrix belizensis. To make matters worse, these birds are also confronted with the destruction of critical habitat due to fire and other anthropogenic disturbance. As is often the case in Belize, many fires are set deliberately to facilitate hunting, land clearing and agriculture. These combined practices create a difficult future for these unique birds in Belize. However, thanks to the efforts of organizations such as the Belize Bird Rescue (BBR), captive breeding programs and artificial nesting boxes are driving the numbers back up. BBR, in coordination with the Belize Forest Department, began a “Captive

15 "Yellow Head Amazon." Belize Bird Rescue. N.P., n.d. Web. 11 July 2017. 15 breed for Release program,” with the intent to breed confiscated illegal-captive birds to produce a releasable population back to the wild.

Methods

To complete a thorough survey of the 22-acre lowland savanna, a multi-staged approach was implemented to collect the most amount of data in an accurate and efficient manner. This approach consisted of two passes over the entire test area. The first pass focused on cover composition, vertical vegetative obstruction, and mid-story data via radial plots and line transects. Once data was collected on these four subjects, a detailed survey of each Pinus caribaea was conducted to collect height, HLC, and LCR. The second pass over the test area was conducted to collect data on Species richness to better understand the diversity in plant life. The combined data has helped to form an understanding of the plant systems at work.

Cover Composition

The purpose of conducting a sampling of cover composition was to record the percentage of horizontal space that is occupied by grass, sedge, forb, woody, pine and palm species less than one meter in height. This procedure also recorded the percentage of horizontal space that is occupied by bare ground and plant matter debris. To survey each 1.5-acre block, nine one-meter by one-meter PVC quadrats were strategically placed over the length of two diagonal lines; the first running from the southeast corner to the northwest corner and the second from the northeast corner to the southwest corner. Five quadrats were placed along the first diagonal line running from the southeast corner to the northwest corner. Quadrat number one was placed 15 meters from the southeast corner to avoid skewed data that may have resulted from edge effect.

Quadrats two through five were then spaced 30 meters apart with the third quadrat landing roughly in the middle of the block. Quadrats six through ten followed the same spacing protocol as line one, the only difference being the omission of a middle quadrat as it would have been redundant (figure 4).

SE corner Figure 4. Quadrat spacing within each 1.5-acre block. All corner quadrats are 15 meters from corners with the remaining quadrats spaced 30 meters apart.

Cover composition observations for each block began from the southeast corner and ended at the southwest corner. A one meter by one meter quadrat was placed at each of the nine quadrat locations and a percent cover class (numbered 1-6) was assigned to each ground cover category and its corresponding abundance. (Table 1).

Ground cover categories Percent cover class G Grass/sedge 0 0%

F Forb 1 1-5%

W Woody 2 6-25%

Pi Pine 3 26-50% Pa Palm 4 51-75% C Coarse debris >2cm. 5 76-95% D Debris < 2cm. 6 96-100%

B Bare ground Tabel 1. Ground cover categories and the percent cover classes.

A percent cover class is used to account for variability in ocular observation. Within each quadrat, an area on 10cm. x 10 cm. represents one percent of the total area. The total area occupied by each cover class category is measured and recorded and repeated nine times for each block (Figure 5).

Figure 5. This quadrat example shows the presence of grass, palm, woody and forb species each occupying 25% of the quadrat. Their corresponding Percent Cover Class would be ‘2’.

Species Richness

The final comprehensive pass of the study area employed the same protocol as the percent cover composition in terms of quadrat placement and spacing. Nine quadrats were placed in each block, the corner quadrats distanced 15 meters from the edges and the remaining quadrats spaced 30 meters apart. Each quadrat was visited and number of present species were counted.

Before this was accomplished, a detailed species catalog was created and a coding system implemented for efficient completion of field notes. Each present species was categorized as either a grass, forb, woody or palm and given an identifying letter/number that corresponds with a species ID catalog (Figure 6). Pines were not included in this richness count as P. caribaea is the only pine species on the site.

Figure 6. A single quadrat with a host of different species present. “Grass species # 1” would be noted at “G1.” “Woody Species # 1” would be noted at “W1.” “Forb Species # 2” would be noted as “F2.”

Pine Data & Mapping

A standard clinometer and DBH tape were used to measure Height, HLC, LCR and DBH of all standing pines in the 22-acre study area. An increment borer was used to determine the age of all living pines. Each pine was then marked with a uniquely numbered aluminum tag so future growth observations may be studied. Height and age data was also collected on all standing snags.

X and Y coordinates of all living pines were collected so precise locations of pines could be mapped for future reference in stand visualization systems. To collect this information, a 300- meter tape was laid along the length (Y axis) of a given block while a 100-meter tape was pulled out across the width (X axis) to the location of each pine. The southwest corner of each block is always (0, 0) in (X, Y) format (Figure 7). By standing directly in front of a target pine along the

Y axis, a Y coordinate could be obtained. Once a Y coordinate was obtained, the 100-meter tape was walked out to the exact location of the tree so an X coordinate could be recorded.

Figure 7. The SW corner always represents (0,0). 300 meter tape is laid along the Y axis and 100 meter tape is laid along the X axis.

Four Meter Transects

Transects were plotted along the length of each block to record the presence of P. caribaea greater than 0.3 meters and less than 1.37 meters in height (Advanced pine regeneration). Also recorded were non-pine woody species greater than or equal to one meter in height and less than two cm at DBH. The transect lines were 4 meters wide and were placed at 15 meters, 30 meters and 45 meters from the southeast corner (Figure 8). All stems that were within a 4 meter width of the observation line and within criteria bounds were counted and used to create an estimate of stems per hectare.

Figure 8. Three transects are placed at 15, 30 and 45 meters from the southwest corner. Each transect is four meters wide.

Vertical Obstruction

Vertical obstruction is a wildlife sampling method used to determine the suitability of surrounding vegetation as potential habitat or hiding place. Measurements were taken using the

21 cover pole method to evaluate vertical cover and vegetative structure. This sampling required the use of a 2 meter high pole with alternating strips of black and white tape at every 10cm

(Figure 9). Only quadrats one, three, five, six and nine received the vertical obstruction sampling. Segments of the pole that are more than 25% obstructed by vegetation are recorded as

“closed” and converted to a total percent of vegetative cover for that quadrat. Segments of the pole that are less than 25% obstructed are recorded as “open.” The cover pole was slid over a short piece of rebar and placed in the center of each quadrat. Observations were made from a distance of 5.6 meters. This was repeated from all cardinal directions. Each quadrat had a total of four observations which were then averaged together to create a percent vertical obstruction. All nine quadrats from a block were then averaged together to create a block average.

Figure 9 A cover pole showing multiple obstructed segments indicating good cover.

Radial Plots

At quadrat three of each block, a 17.8 meter radial plot was created to record the presence of woody material greater than or equal to 1.37 meters in height and greater than or equal to 2 cm. at DBH. A piece of rebar was placed at the center of quadrat three and a 100m. tape was pulled to a length of 17.8 meters. A circle was walked around the center and the species, diameter and height of eligible plants were recorded.

Results

Cover Composition

The initial survey of the study area collected data on cover composition to understand the balance of plant life within the savanna. As predicted, grasses/sedges are the dominant form of cover on the savanna. After completing observations on 135 quadrats over 22 acres, it was determined that grasses/sedge covered 76-95% of area within the quadrats. Forb species, woody species and fine debris covered 1-5% of the total quadrats each. Bare ground also had a significant role in the savanna, occupying 6-25% of the area within the quadrats (Table 2).

However, the cover composition categories of palm, pine and coarse debris were infrequently detected within the quadrats thus leading to a 0% average among the 22 acres.

Table 2. Shows the distribution of cover composition among the 8 cover composition categories. Ground Cover Categories Percent cover Grass/ Sedge 76-95% Forb 1-5% Woody 1-5% Palm 0% Pine 0% Coarse Debris 0% Fine Debris 1-5% Bare Ground 6-25%

Species Richness

In total, 18 woody species (including P. caribaea), 23 forb species and two sedge species were identified and cataloged within the 22-acre savanna. There are still five unidentified forb species, one unidentified wood species and 9 unidentified grass/sedge species within the 22-acre study area. Identified and unidentified species together totals to 19 woody species, 28 forb species and 11 grass/sedge species cataloged within the 22-acre study area. Collectively, this is

58 plant species that have been cataloged into the savanna plant database.

On average, each block contained five grass species, six forb species and six wood species for an average of 17 different plant species per block. Unidentified sedge species # 3

(G3) is the mostly widely dispersed species of sedge over the 22-acre study area having been present in 89% of the total 135 quadrats. Oxalis frutescens is the most widely dispersed woody species within the study area having been present in 32% of the total 135 quadrats. Diodela apiculate is the most widely dispersed forb species within the study area having been present in

50% of the total 135 quadrats (Table 3/ Figure 11). Since the exact area of an individual species wasn’t recorded within each quadrat, a conclusion cannot be made concerning the total cover composition of any one species within the study area. This can only be accomplished with broad categories; grass, forb, wood etc.

Table 3. Shows the top three species from each category and the percent of total quadrats they were present in. (G1- G3) Unidentified grass species. (W16) Oxalis frutescens. (UW3) Unidentified wood species. (W1) Gymnopodium floribundum. (F6) Diodela apiculate. (F15) Cassytha filiformis. (F1) Agalinis harperi.

Grass % of total Woody % of total Forb % of total quadrats quadrats quadrats G1 70% W16 32% F6 50% G2 88% UW3 27% F15 33% G3 89% W1 19% F1 21%

Figure 11- Diodela apiculate Oxalis frutescens Unidentified sedge # 3 (G3)

Pine Data

Across the 22-acre study plot, 145 Pinus caribaea were counted and tagged with aluminum labels so that monitoring may continue into the future. Of the 145 pines, 26 cores were extracted to determine age and five-year incremental growth. The two tallest pines in each block were selected for core extractions. Blocks twelve and six were the only exceptions as they each contained only one Pinus caribaea each. Block ten contained zero pine trees. The average age of the 26 pines was 49 years old with an average five-year incremental growth of 0.5cm. Average

HLC, height, DBH, LCR, BA and TPA are shown below (Table 4).

Table 4. Demographic information for living pines Average HLC across all 15 blocks 3.4 m 5.7 m Average Height 12.9 cm Average DBH 0.4 Average LCR 0.16 m2 Average BA 15 Average pines/hectare 35 Average advanced pine regeneration/ hectare

Four Meter Transect

Advanced pine regeneration per hectare was 35. These were pines that were greater than 0.3 meters in height and less than 1.37 meters. Hardwood stems, not including pine trees, averaged

274 stems per hectare. These stems were greater than one meter in height and less than two centimeters at DBH. Total average stems per hectare including pine regeneration is 309 stems per hectare. (Table 5)

Table 5. Pine and hardwood density Advanced pine regeneration/hectare 35

Hardwood stems/hectare 274

Total stems per hectare 309

Vertical Obstruction

Figure 12 shows vertical vegetative obstruction was variable among the blocks, providing a multitude of habitat and cover opportunities for wildlife. Though no wildlife data was officially collected, Tapir paths were observed on the west side of the savanna near to the carved drainages.

Percent Vertical Obstruction by block

35% 30% 25% 20% 15% 10% 5% 0% Block Block Block Block Block Block Block Block Block Block Block Block Block Block Block 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Figure 12. Distribution of vertical vegetative obstruction across all 15 blocks.

Radial Plot

Radial plot observations recorded 11 blocks with woody material that fell within the study guidelines. Four of the 15 blocks may have contained woody material but was not recorded within the plot. Table 6 shows averages of the study area.

Table 6. Woody material greater than or equal to 1.37 meters in height and greater than or equal to 2cm. in diameter at DBH BA/hectare 0.34 m2 10.6 cm. Average diameter 4.7 m Average height

Snags

Dead but standing pines (snags) were included in this study to gauge potential wildlife habitat.

Along with height, DBH, BA and snags per hectare, a decay class (Table 7) was also assigned to each snag to categorize the varying states of decay (Table 8).

TABLE 7. Decay class table shows characteristics of decayed trees listed one through four. One being least decayed and four being most decayed. Snag decay class: 1-4 Characteristic 1 2 3 4 Branches 80-100% Few- no branches Limb stubs-None None

W/≥50% Height: ≤30% W/ <50% Bark 80-100% 30-80% Height: >80% <80%

Full- Height broken top Broken top Broken top-50% <50%

Table 8. Demographic information for snags 2.4 Average Decay class 4.8 m Average height 15.5 cm Average DBH 0.05 m2 BA/ hectare 3 SPH Snags/hectare

Conclusion

In 1993 168,000 ha of savanna were recorded throughout the entire country of Belize.

These savannas are the most northerly examples of lowland savannas in the Americas and represent a landscape of diversity and resilience. Many savannas throughout Belize still remain botanically unexplored leaving their conservation value unknown. In addition, human caused wildfires are spreading with alarming speed, hindering the growth of pine which is both a profitable timber species and a vital wildlife component. Without proper knowledge of how fire best interacts within savanna ecosystems, it will be difficult to manage these savannas in a way that is beneficial to both humans and the local environment.

Cover composition results from this study revealed that graminoids are the most widely spread and abundant plant form in these savannas. Not only do these systems rely on these fuels to carry necessary regenerating fires but their carbon sequestration abilities deserve further investigation. Total species richness throughout the study area totaled 58 unique species including three terrestrial orchid varieties and one carnivorous species. Further investigation is

28 also required regarding P. caribaea as infestations of termites and Southern pine bark beetle will have a lasting effect on the longevity of this species.

Today in Belize, between 22-27% of remaining lowland savannas reside within protected areas. These privately-operated reserves have proven to be a vital component of the conservation framework within Belize and will continue to set the standard for efficacy and sustainability.

Since 1980, 20,000 ha of savanna have been converted to industrial use. While it is important to advocate for the protection of these areas it is also important to consider the economic benefits

Belize has gained from these transitions. Many of these savannas have been converted to agricultural operations which now represent more than a tenth of the country’s GDP. Not only do these operations bring in millions in revenue each year but they also represent a steady source of employment in a country with 12.9% unemployment. However, with tourism industry employment representing 59.9% of GDP it is vitally important to consider the future of all resources especially those that are least understood.

Further Research

Careful inventory of this 22-acre research plot revealed an enormous level of diversity in the understory plants, providing unique habitat and placing important cultural value within lowland savannas. The cooperative work that went into this inventory has provided a robust body of work that can now be employed for further research, particularly in respect to fire, disturbance and successional ecology. The motivation behind this research was to create a clearer understanding of how Belizean lowland savannas react to varying fire regimes and to which regime promotes native understory plant diversity in the long run. Going into the future, it is the hope that this body of work along with the plant identification deliverables and sampling protocol instructions will enable further enquiry into the functions of healthy ecosystems in Belize. By providing detailed plant information and easy to follow sampling protocols, data collection should be streamlined, allowing for the introduction of prescription fire to the landscape which can then be observed and analyzed. In Belize today, an abundance of unplanned ignitions have created habitat loss, agricultural losses and a multitude of other setbacks that left un treated will continue to negatively impact the lives of Belizeans. By providing preliminary data, cooperative research with the Belize zoo and the Tropical Education Center can continue. A wonderful opportunity has been provided with the establishment of this project and it will only be through cooperative learning that more can be understood about the interactions of fire in lowland pine savannas of Belize.

Work Cited 1. Bridgewater, Sam, Iain Cameron, and Peter Furley. "Results of Darwin Initiative Project 17-022 and Implications for Savanna Conservation.” Http://www.eeo.ed.ac.uk/sea-belize/outputs/progress_reports/savannareport.pdf. Belize Tropical Forest Studies (BTFS), June 2012. Web. 2. Brown, K.K. (2000) Introduction and fire regimes. Wildland fires in Ecosystems: Effect of fire on Flora, General Technical report RMRS-GTR-42-Vol-2. USDA Forest Service, Intermountain, Forest and Range Experiment Station, Ogden, UT.

3. “Fire Management” | Toledo Institute for Development and Environment. TIDE, 2015. Web.

4. Foster, R. (2017, June 26). Personal interview

5. Meerman, J C, and W Sabido. “Central American Ecosystems Map: Belize 2001.”

Http://Biological-Diversity.info/Downloads/Volume_Iweb_s.Pdf, Programme for Belize, biological-diversity.info/Downloads/Volume_Iweb_s.

6. Meerman, J. C., and W. Sabido. "Central American Ecosystems Map: Belize Volume II." (2001): Web. http://biological-diversity.info/Downloads/Volume_IIweb_s.pdf

7. Myer, Ronald L., and Dante Arturo Rodriguez-Trejo. Fire in Tropical Ecosystems. N.P.: Print.

8. Myers, R.L (2006) Living with Fire: Sustaining Ecosystems and Livelihoods through Integrated Fire Management. The Nature Conservancy, Global Fire Initiative, Arlington, VA

9. "The World Factbook: BELIZE." Central Intelligence Agency. Central Intelligence Agency, 26 June 2017. Web. 11 July 2017.

10. "Yellow Head Amazon." Belize Bird Rescue. N.P., n.d. Web. 11 July 2017.