Caribbean Marine Biodiversity Program (CMBP)

Home , Conocarpus, Laguncularia racemosa, Rhizophora mangle

Assessment of Mangroves in Bajo Yuna National Park,

Dominican Republic

Prepared by: Landy Cyprien Technical Report Submitted November 3, 2017 This report is made possible by the generous support of the American people through the United States Agency for International Development (USAID). The contents are the responsibility of The Nature Conservancy and its partners (CEBSE, FOPROBIM, CCAM, and SusGren) and do not necessarily reflect the views of USAID or the United States Government.

Contents

Executive Summary ...... 5

Background ...... 7

Materials and Methods ...... 9

Results ...... 12

Habitat Description ...... 13 Mangrove Inventory ...... 13 Sector I: Bajo Yuna ...... 14 Sector II: Los Corozos ...... 30 Mapping the Mangroves ...... 34 Species Identification ...... 37 Water Quality Assessment ...... 40

Discussion and Recommendations ...... 40

Conclusion ...... 42

Literature Cited ...... 43

Annexes ...... 45

List of Tables

Table 1: Description of disturbance factors identified in Samaná Bay ...... 11 Table 2: Average size of mangroves sampled in Bajo Yuna and Los Corozos, Samana Bay, Dominican Republic ...... 13 Table 3: Data on mangroves in plot #1, sector I, Bajo Yuna ...... 15 Table 4: Data on mangroves in plot #2, sector I ...... 15 Table 5: Data on mangroves in plot #3, sector I ...... 16 Table 6: Data on mangroves in plot #4, sector I ...... 17 Table 7: Data on mangroves in plot #5, sector I ...... 17 Table 8: Data on mangroves in plot #6, sector I ...... 18 Table 9: Data on mangroves in plot #7, sector I ...... 18 Table 10: Data on mangroves in plot #8, sector I ...... 19 Table 11: Data on mangroves in plot #9, sector I ...... 20 Table 12: Data on mangroves in plot #10, sector I ...... 20 Table 13: Data on mangroves in plot #11, sector I ...... 21 Table 14: Data on mangroves in plot #12, sector I ...... 21 Table 15: Data on mangroves in plot #13, sector I ...... 22 Table 16: Data on mangroves in plot #14, sector I ...... 23 Table 17: Data on mangroves in plot #15, sector I ...... 23 Table 18: Data on mangroves in plot #16, sector I ...... 24 Table 19: Data on mangroves in plot #17, sector I ...... 24 Table 20: Data on mangroves in plot #22, sector I ...... 25 Table 21: Data on mangroves in plot #23, sector I ...... 26 Table 22: Data on mangroves in plot #24, sector I ...... 26 Table 23: Data on mangroves in plot #25, sector I ...... 27 Table 24: Data on mangroves in plot #26, sector I ...... 27 Table 25: Data on mangroves in plot #27, sector I ...... 28 Table 26: Data on mangroves in plot #28, sector I ...... 29 Table 27: Data on mangroves in plot #29, sector I ...... 29 Table 28: Data on mangroves in plot #30, sector I ...... 30 Table 29: Data on mangroves in plot #18, sector II, Los Corozos ...... 31 Table 30: Data on mangroves in plot #19, sector II ...... 32 Table 31: Data on mangroves in plot #20, sector II ...... 33 Table 32: Data on mangroves in plot #21, sector II ...... 33 Table 33: Common and scientific names of notable plants at Samaná Bay ...... 37 Table 34: List of birds and their conservation status (IUCN) ...... 38 Table 35: Common and scientific names of crustaceans and mollusks identified ...... 39

List of figures Figure 1: Distribution of sampling sites in Bajo Yuna National Park and Los Corozos, Samaná Bay ...... 9 Figure 2: Satellite image of sector I (Bajo Yuna National Park), Samaná Bay, showing the distribution of survey sites ...... 14 Figure 3: Satellite image of Los Corozos ……………………………………………………………………………………31 Figure 4: Density of the four mangrove species ...... 34 Figure 5: Diameter at breast height (DBH) of the four mangrove species ...... 35 Figure 6: Height of the four mangrove species...... 37

List of Annexes

Annex 1: Crab in Samaná Bay (Uca sp.)...... 45 Annex 2: Crab in Samaná Bay (Aratus pisonii) ...... 45 Annex 3: Birds around Rio Barracote ...... 46 Annex 4: Birds: Fregata magnificens ...... 46 Annex 5: Mangrove plantlets around Rio Barracote ...... 47 Annex 6: Fishers in Samaná Bay around Rio Yuna ...... 47 Annex 7: Solid waste (bottles and other trash) under some red mangrove trees ...... 48 Annex 8: Solid waste on the beach in front of the mangrove area in Bayo Yuna ...... 48 Annex 9: Rhabdadenia biflora ...... 49 Annex 10: Mangrove oyster ...... 49 Annex 11: Charcoal production around the mangroves in Los Corozos ...... 50 Annex 12: View from the mangrove area in Los Corozos ...... 50 Annex 13: View of the mangrove area near Sanchez ...... 51 Annex 14: Pasture near the mangrove ...... 51 Annex 15: Mangrove around Rio Barracote ...... 52

Executive Summary

The Caribbean Marine Biodiversity Program (CMBP), funded by USAID, aims to reduce threats to marine and coastal biodiversity in priority areas in the Caribbean, such as coral reefs, mangroves, and seagrass beds. The goals of this work are to achieve sustained biodiversity conservation, maintain critical ecosystem services, and realize tangible improvements in human wellbeing for communities adjacent to marine protected areas (MPAs) and marine managed areas (MMAs). To achieve these goals, four steps must be completed: 1. Create an environment that will enable long-term MPA success. 2. Develop effective marine spatial plans (MSPs) and seascape governance mechanisms. 3. Create a more sustainable fisheries sector by maximizing the fishery benefits of MPAs/MMAs, promoting innovative fishery management actions, and promoting sustainable livelihoods. 4. Maintain effective management and governance of MPAs/MMAs.

To help achieve the goals of the CMBP, mangrove restoration, monitoring, and assessments are being done in targeted CMBP seascapes to sustain and restore marine and coastal biodiversity. Mangroves are very valuable ecologically, as they play a critical role in protecting coastal shorelines and provide nursery and feeding grounds for commercially important marine species that contribute to local economies. Regular mangrove assessments can reveal the health status of mangrove populations and their surrounding ecosystem. Assessments should cover threats impacting mangroves as well as changes (i.e., loss or increase) in mangrove biomass and growth. Depending on the type and level of threats detected, suitable conservation methods can then be applied.

This study aimed to conduct ground-truthing of 30 mangrove sites throughout the Manglares del Bajo Yuna Parque Nacional (BYPN), or Bajo Yuna National Park, in the Dominican Republic to determine the health status of the mangroves and identify suitable conservation actions to preserve this ecosystem. The consultant analyzed changes in the biophysical conditions of the

different mangrove species in the BYPN, relative to conditions reported from previous field work, and provided data to improve the classification accuracy of mangroves for satellite imagery representation. Four species of mangroves were identified: black mangrove (Avicennia germinans), white mangrove (Laguncularia racemosa), buttonwood mangrove (Conocarpus erectus), and red mangrove (Rhizophora mangle).

R. mangle was the most abundant species (6,180 trees/ha), followed by L. racemosa (4,106 trees/ha) and A. germinans (826 trees/ha). The buttonwood mangrove (C. erectus) had the lowest density of all the species and was observed at only two of the 30 sites, with an average density of 32 trees/ha.

The black mangrove was the largest according to diameter at breast height (DBH) and height across 30 plots in two sectors (average DBH 36 cm and average height 24 m). Red mangroves were the second largest with an average DBH of 16.51 cm and height of 11.87 m. The white mangrove was the third largest, with an average DBH of 7.52 cm and average height of 7.67 m. The buttonwood mangrove had an average DBH of around 3.25 cm and an average height of 7 m.

The mangroves of Bajo Yuna, Samaná Bay, are in relatively good condition, as in many places there were no significant signs of disturbance or pollution. In the area close to the Barracote River, mangroves were undergoing a process of self-regeneration and natural growth, with previously damaged plants growing again. This area is also heavily influenced by the movement of the tides and sedimentation. Thousands of plantlets, mostly R. mangle, were observed in that specific part of the Bay. Inside the mangrove area, close to the Yuna River, many white mangrove plantlets were also visible.

Several grazed grasslands were seen around the mouth of the Yuna River. Fishing is one of the main economic activities in the lagoon, with shrimp, blue crab, and mangrove snappers being the main species caught. Hundreds of species compose the coastal and marine biota of the Bay, among them many crustaceans and mollusks, such as the common white shrimp and pearl oyster.

A major threat to the ecosystem is external activities, such as waste disposal from the towns in Samaná Bay and the municipal dump of Sanchez, located on the northern fringes of the core mangrove area. Multiple plastic bottles were observed across the beaches and among the roots of the mangrove plants. A charcoal disposal site was also observed around Los Corozos. Despite this, the mangroves in this area seem to be in excellent health. The mangroves at Los Corozos are also somewhat protected from anthropogenic influences by a dense thicket of trees bordering the mangrove forest on the landward side.

Five coastal plants associated with mangroves, 30 species of birds (including two endemic species, Coccyzus longirostris and Melanerpes striatus), two species of crustaceans, and three species of mollusks were identified within the sampling area. The salinity in Samaná Bay ranged between 0.5 and 25 ppt, corresponding with the modal salinity of open water, while the salinity around the Yuna and Barracote Rivers (the riverine edge and fringing area) was much lower, ranging from approximately 0.5 to 10 ppt. The pH in Samaná Bay ranged from 7.2 to 8.5, and temperature readings fluctuated at the sites between 24°C and 32°C.

Based on these observations, it is recommended that CMBP invests in doing rehabilitation or restoration activities at these sites. Instead, CMBP should focus on educating residents in and around the area about the value of mangroves and their importance to the communities. Efforts to improve awareness and education should consider the mangrove ecosystem as a whole to dispel misconceptions about its importance. In addition, solid waste management activities should be implemented in communities in Samaná Bay.

Background

The CMBP team developed a performance monitoring plan to guide monitoring of the program, using a core set of performance indicators for project targets, data collection, and analysis. The plan is used to:

1) monitor quantitative and qualitative impacts and outcomes,

2) track and report on CMBP progress,

3) evaluate CMBP success, and

4) inform adaptive management during program implementation.

One indicator was selected to track changes in biophysical conditions of marine and coastal environments in each of the seascapes: the number of hectares (ha) of natural resources (represented by coral reefs and mangroves) that showed improved biophysical conditions as a result of United States government assistance. To determine this number, mangrove monitoring was performed, using a combination of remote sensing technology and field surveys to provide in-depth information on the spatial extent and biophysical conditions of the forest.

The mangroves of Bajo Yuna are located on the western end of Samaná Bay, one of the largest semi-closed bays in the Caribbean. They form a highly productive ecosystem with a rich diversity of flora and fauna, including many endemic species. This is a Ramsar site, and since 2013 a National Park, indicating its international importance for biodiversity. The most recently performed assessment of the mangroves (2015–2016) showed that their spatial extent had declined in certain sections of Bajo Yuna since 2003, as a result of aquaculture activities and a landfill adjacent to the northern boundaries. However, in other sections of the park, there was a notable increase in mangrove cover due to sediment deposition around the mouth of Barracote River. Considering these changes, mangrove reforestation plans are now being crafted to restore some of the at-risk vegetation in the northern sections. Monitoring activities will assess any recent changes in the cover of the mangrove forest and its biophysical condition, compared with pre-existing data, as well as helping to guide site selection for reforestation activities in the park. Although this study was conducted after the major hurricanes Irma and Maria passed through the area, there were no visible signs of storm impact in the areas.

Materials and Methods

A vegetation field guide was created to facilitate the identification of species in the field. For each taxon, a checklist of expected species was compiled according to the World Atlas of

Mangroves (Spalding et al., 2010). Other books were consulted, particularly the Guide Méthodologique pour la Cartographie des Mangroves de l’Outre-Mer Français (Taureau et al., 2015). In addition, we prepared a digital field guide to identify mollusks and crustaceans by using information from the Internet (IUCN website) and consulting “Spatial Patterns of Biomass and Aboveground Net Primary Productivity in a Mangrove Ecosystem in the Dominican Republic” (Sherman et al., 2003).

The study area was limited to the coastal wetlands of BYPN and Los Corozos in the Dominican Republic (Lat: 19° 10.516'N and Long: 69° 37.827’O) (Fig. 1). Data collection at each site took an average of three hours. Four to five sites per day were sampled, depending on the accessibility of areas. Figure 1 shows the distribution of sample sites throughout the park.

A preliminary field assessment was performed using satellite imagery to study the spatial distribution of the predetermined sites. Mangroves were surveyed in 30 sites, each measuring 250 m² (25 x 10). In some areas, where the quadrats were difficult to demarcate, a 100-m transect line was laid along the mangroves. This method has been used for sites with dense thickets of trees, only accessible by boat along rills. In these areas, roots of the mangroves, mostly R. mangle, were immersed in mud more than 60 cm deep. Several parameters were identified and measured, such as species of mangrove and estimated canopy cover.

The number of plants per species was determined, using the field guide, and recorded for each quadrat. Several pictures of associated flora (leaf, flower, seed, root, and fruit) and samples were taken to put together a herbarium, which allowed for further identification after the field work component was complete. The phenology (flowering, fructification, and seeding) of the plants was also recorded.

Figure 1: Distribution of the sampling sites in Bajo Yuna National Park and Los Corozos, Samaná Bay

At each site, mangrove stand characteristics were documented (canopy cover, percent cover, and tree heights). The canopy cover was estimated as a percentage from 0% to 25% for areas where the canopy cover was less significant, from 25% to 50% in areas with partial cover, 50% to 75% where vegetation was very dense and tree crowns were extensive, and 75% to 100% where the tree crowns were consistently overlapping.

The height of the mangroves was measured from the ground to the crown. For each species, we calculated the average height of the trees; we also calculated the average DBH at 1.35 m from the ground for each species.

In addition to the mangrove identification and measurement, information about the overall habitat was recorded, such as the type of substratum, associated species, and water quality.

Where tree roots were immersed, pH, salinity, and temperature of the water were measured using a multi-parameter tester. Flora of the mangrove ecosystem were identified by examining their morphological characteristics, while fauna (i.e., birds, mollusks, and crustaceans) were listed based on sighting, referencing documents on wildlife that frequent the area, and consulting local individuals.

To estimate plot health, we used a quantitative scale from 1 to 5, described in Moore (2014), in which a score of 1 = poor and 5 = exceptional, as explained in the Baseline Ecological Inventory for Three Bays National Park, Haiti (2015). To evaluate disturbance level, we ranked plots according to the following scale. A ranking of “Good” implies little to no evidence of disturbance (e.g., cutting/harvest) or die-back; forest cover is > 50%, trees and shrubs are reproducing and exhibit strong evidence of stand seedling recruitment; and there is an opportunity for stand expansion or migration. A ranking of “Fair” indicates some evidence of disturbance; forest cover is < 50% but > 25%; there is some evidence of seedling recruitment, but stand expansion or migration is likely limited. Finally, a ranking of “Poor” means that there is abundant evidence of disturbance; forest cover is < 25%; there is no evidence of seedling recruitment; and stand expansion or migration appears impossible. In contrast with Moore, authors like Ellison and Farnsworth (1996) considered four classes of anthropogenic disturbances: 1) extractive uses of mangrove trees and fauna, 2) reclamation of mangrove habitat for non-extractive uses, 3) pollution of the mangrove area, and 4) damage to mangroves due to climate change. It is clear from the literature that many factors affect the level of disturbance (Table 1). Therefore, we scored areas out of a possible five points, with five indicating a healthy and undamaged area, and lower numbers indicating more disturbance.

Table 1: Description of disturbance factors identified in Samaná Bay Disturbance factor Comments Pollution Soil and water pollution Solid waste (such as plastic Need low-cost disposal options for local bottles) community Withering Mortality

Deforestation/mangrove cutting Visible sign of cutting: piles of wood, charcoal activity, sectioned trunks Regeneration Presence of plantlets or young trees Agriculture Nearby agriculture area Barrier Presence of mangrove-made barrier for fishing activities Land conversion Mostly for salt mining and agriculture Settlement proximity Houses nearby Livestock proximity Cattle nearby Fishing Boats, nets, fish vendors, crab traps, and so on nearby

The spatial distribution of plants (density per hectare), average DBH, and average tree height were analyzed using ESRI ArcGis.

Results

Habitat Description

Samaná Bay is the largest semi-enclosed bay in the Caribbean (over 75,000 hectares), and contains the most extensive mangroves and shrimp fisheries in the Dominican Republic. The Samaná Bay mangrove forest is considered one of the best study sites for forest dynamics; it is an ideal setting in which to evaluate the environmental controls on mangrove forest development and productivity according to Kauffman and others (2014). This area is crossed by a set of channels, mostly muddy rills, that join the Yuna River before reaching the sea. The Yuna River and the Barracote River are the two main rivers in the sampling area; they are relatively easy to access from the sea depending on the tide. The Yuna and Barracote rivers result in sedimentation that prevents the development of marine grasses; however, this area is suitable for natural mangrove nurseries. The open water provides important habitat for bird species including pelicans, green herons, white ibis, little blue herons, tricolored herons, and snowy egrets. The mangrove system provides habitat for abundant fiddler crabs (Uca sp.) and mangrove crabs (Aratus pisonii). The fringing area also provides habitat for mangrove and pearl oysters (Crassostrea rhizophorae and Pinctada sp.).

Mangrove Inventory

Four species of mangroves were identified in the study area: black mangrove (Avicennia germinans), white mangrove (Laguncularia racemosa), red mangrove (Rhizophora mangle), and buttonwood mangrove (Conocarpus erectus). The forest was dominated by red and white mangroves with a small proportion of black mangroves. The average measurements of the species are listed in Table 2.

Table 2: Average size of mangroves sampled in Bajo Yuna and Los Corozos, Samaná Bay, Dominican Republic

Species Scientific Name Average DBH (cm) Average Height (m)

Black mangrove Avicennia germinans 19.28 12.86

White mangrove Laguncularia racemosa 7.52 7.67

Red mangrove Rhizophora mangle 11.87 16.51

Buttonwood mangrove Conocarpus erectus 3.25

The mangrove habitats in Bajo Yuna and Los Corozos were in good condition, though some areas showed signs of current and continuing deterioration. In the interior portions of the mangrove habitat, there were many places where the mangrove trees had been cut or had fallen. Tall R. mangle and L. racemosa trees (growing up to 30 m in height with a DBH of 60 cm) were also observed in several areas close to the Yuna River. C. erectus were observed on the upland edges of the mangrove habitat, while the other species were observed in various habitats, such as inland shallow marshes and shrub.

The plots located close to beaches were very polluted with solid waste, including plastic bottles, straws, and debris. Mangroves close to beach sites are threatened by wood harvesting, and old cut mangrove roots were seen in several areas. If this activity continues and becomes more

widespread, the quality of the ecosystem may deteriorate. In Los Corozos, charcoal disposal was also observed close to one of the sample sites.

Sector I: Bajo Yuna

Bajo Yuna is the largest area of the study, spanning 3,456 ha and including 26 of 30 sites sampled (Figure 2). This sector contains land close to and between the Yuna River and the Barracote River, as well as areas where tourism, fishing, and shrimp harvesting occurs. The highest density of trees can be found in this region. Various stages of natural regeneration were observed in some areas. Of particular importance were the plantlets observed in the fringing area across the mouth of the Figure 2: Satellite image of sector I (Bajo Yuna National Park), Samana Bay, showing the distribution of survey sites Barracote River. Within the same area, there were many fallen dead mangrove trees. Based on the condition of the barks, these downed trees likely fell before the passage of Hurricanes Maria and Irma. The mangroves did not show any sign of recent disturbance due to hurricanes.

Table 3: Data on mangroves in plot #1, sector I, Bajo Yuna

Species Number Height Average Density % of Total, by of Plants (m) DBH (cm) (trees/ha) Species

Avicennia germinans 35 0.8 <2 1,400 56

Rhizophora mangle 2 25 21 80 3

Laguncularia racemosa 26 0.5 <2 1,040 41

Conocarpus erectus 0 0 0 0 0

Total 63 - - 2,520 100

As shown in Table 3, plot #1 had a total of 63 trees, 56% of which were black mangrove, 41% white mangrove, and 3% red mangrove. The density was calculated at 2,520 trees/ha. The overall canopy cover was estimated to be between 0% and 25%. Around this site, coconut husks from nearby coconut trees, two species of crabs, and many other plants, such as Rhabdadenia biflora and Acrostichum aureum, were observed. The overall health based on the disturbance factors present was estimated at 4/5. While the mangrove trees in this plot are not directly threatened, the footprint of human activities is clear, and changes in the area may affect the productivity of the ecosystem.

Table 4: Data on mangroves in plot #2, sector I

Species Number Height Average Density % of Total, by of Plants (m) DBH (cm) (trees/ha) Species

Avicennia germinans 18 0.5 <2 720 39

Rhizophora mangle 13 1.5 <2 520 28

Laguncularia racemosa 11 2.5 3 440 24

Conocarpus erectus 4 3 3.5 160 9

Total 46 - - 1,840 100

As shown in Table 4, plot #2 had a total of 46 trees with an average DBH of 3 cm for the white mangrove and 3.5 cm for the buttonwood mangrove, while the DBH for the other species were under 2 cm. The density was calculated to be 1,840 trees/ha. This site is located around a relatively commonly used fishing area. The health of the plot was estimated to be excellent (5/5).

Table 5: Data on mangroves in plot #3, sector I

Species Number Height Average Density % of Total, by of Plants (m) DBH (cm) (trees/ha) Species

Avicennia germinans 0 0 0 0 0

Rhizophora mangle 32 8 31.5 1,280 100

Laguncularia racemosa 0 0 0 0 0

Conocarpus erectus 0 0 0 0 0

Total 32 - - 1,280 100

As shown in Table 5, plot #3 had a total of 32 trees, all red mangroves, with an average DBH of 31.5 cm. The average tree height for this plot was 8 m. The density was calculated to be 1,280 trees/ha, and the canopy cover was estimated to be between 50% and 75%. The health of this plot was estimated to be relatively poor (2/5), as solid waste was observed around the site along the coast.

Table 6: Data on mangroves in plot #4, sector I

Species Number Height Average Density % of Total, by of Plants (m) DBH (cm) (trees/ha) Species

Avicennia germinans 0 0 0 0 0

Rhizophora mangle 52 14 22 2,080 70

Laguncularia racemosa 22 10 12 880 30

Conocarpus erectus 0 0 0 0 0

Total 74 - - 2,960 100

Plot #4 contained 74 trees, including red mangroves (70% coverage, DBH calculated at 22 cm) and white mangroves (30% coverage, DBH of 12 cm). The average tree height in this plot was 12 m and the canopy cover was estimated to be between 0% and 25%. The total density was 2,960 trees/ha, with white mangroves showing a lower density of 880 trees/ha. This site had a few signs of anthropogenic influence; we observed a few plastic bags and bottles, some old cut marks on trunks, and many signs of fishing activities, such as active fish nets and abandoned boats. As a result, the plot health was estimated at 3/5.

Table 7: Data on mangroves in plot #5, sector I

Species Number Height Average Density % of Total, by of Plants (m) DBH (cm) (trees/ha) Species

Avicennia germinans 120 0.4 <2 4,800 100 0 0 0 0 Rhizophora mangle 0

Laguncularia racemosa 0 0 0 0 0 0 0 0 0 0 Conocarpus erectus

Total 120 - - 4,800 100

As shown in Table 7, plot #5 contained 120 trees, all black mangroves, with an average DBH under 2 cm. The trees in this plot were an average 0.4 m in height. There was 4,800 trees/ha, and the canopy cover was estimated to be between 50% and 75%. The health of the plot was estimated to be excellent (4/5); however, solid waste was observed nearby, along the coast. This site was inundated and at risk of pollution from the waste on the shoreline drifting in.

Table 8: Data on mangroves in plot #6, sector I

Species Number Height Average Density % of Total, by of Plants (m) DBH (cm) (trees/ha) Species

Avicennia germinans 0 0 0 0 0

Rhizophora mangle 39 13 23 1,560 66

Laguncularia racemosa 20 23 17.5 800 34

Conocarpus erectus 0 0 0 0 0

Total 59 - - 2,360 100

Plot #6 had a total of 59 trees with an average DBH of 20 cm, 34% of which were white mangrove and 66% of which were red mangrove. The mean tree height for this plot was 18 m, with white mangroves being the tallest. The canopy cover was estimated to be between 25% and 50%. The density was 2,360 trees/ha. Anthropogenic interference was apparent, as garbage heaps and cut trunks were present. Therefore, the level of health was categorized as 2/5.

Table 9: Data on mangroves in plot #7, sector I

Species Number Height Average Density % of Total, by of Plants (m) DBH (cm) (trees/ha) Species

Avicennia germinans 6 8 8 240 3

Rhizophora mangle 15 10 15 600 9

Laguncularia racemosa 150 0.4 <2 6,000 88

Conocarpus erectus 0 0 0 0 0

Total 171 - - 6,840 100

As shown in Table 9, plot #7 contained 171 trees, 88% of which were white mangroves, 3% black mangroves, and 9% red mangroves. Red mangroves were the largest, with an average height of 10 m and average DBH of 15 cm. The canopy cover was estimated to be between 25% and 50%. The density was 6,840 trees/ha. The health of this plot was 3/5.

Table 10: Data on mangroves in plot #8, sector I

Species Number Height (m) Average Density % of Total, by of Plants DBH (cm) (trees/ha) Species

Avicennia germinans 0 0 0 0 0

Rhizophora mangle 2,450 5 2.5 98,000 58

Laguncularia racemosa 1,800 5 3 72,000 42

Conocarpus erectus 0 0 0 0 0

Total 4,250 - - 170,000 100

The vegetation in and around plot #8, located at the seaward fringes of the forest, was quite dense and healthy, with a total of 4,250 trees and an average DBH of 2.7 cm. The trees were 58% red mangrove and 42% white mangrove. The canopy cover was estimated to be between 50% and 75%. The density was calculated as 170,000 trees/ha. The health of this plot was assigned 5/5.

Table 11: Data on mangroves in plot #9, sector I

Species Number Height Average Density % of Total, by of Plants (m) DBH (cm) (trees/ha) Species

Avicennia germinans 0 0 0 0 0

Rhizophora mangle 48 1 <2 1,920 38.5

Laguncularia racemosa 80 2 <2 3,200 62.5

Conocarpus erectus 0 0 0 0 0

Total 128 - - 5,120 100

Table 11 shows that plot #9 contained 128 trees. The canopy cover was estimated between 0% and 25%. The density was 5,120 trees/ha. Many plantlets and parent trees were observed at this site. A cattle operation and grazing land were also spotted within 250 m of the plot.

Table 12: Data on mangroves in plot #10, sector I

Species Number Height Average Density % of Total, by of Plants (m) DBH (cm) (trees/ha) Species

Avicennia germinans 300 7 4 12,000 15

Rhizophora mangle 1,150 10 6 46,000 57.5

Laguncularia racemosa 550 9 5 22,000 27.5

Conocarpus erectus 0 0 0 0 0

Total 2,000 - - 80,000 100

As shown in Table 12, plot #10 contained 2,000 trees, 57.5% of which were red mangroves, 27.5% white mangroves, and 15% black mangroves. The average DBH was 4 cm for black and 6 cm for red mangroves. The average tree height for this plot was 9 m. The density was calculated to be 80,000 trees/ha. Although no solid waste was observed in the immediate vicinity of the plot, cattle and horses were observed grazing close by. The health was therefore categorized as a 4/5.

Table 13: Data on mangroves in plot #11, sector I

Species Number of Height Average Density % of Total, by Plants (m) DBH (cm) (trees/ha) Species

Avicennia germinans 0 0 0 0 0

Rhizophora mangle 0 0 0 0 0

Laguncularia racemosa 50 0.8 <2 2,000 100

Conocarpus erectus 0 0 0 0 0

Total 50 - - 2,000 100

Plot #11 contained a total of 50 trees, all white mangroves, with an average height of 0.8 m. The density was 2,000 trees/ha. The plot was located in a marshy area with many crabs and parent trees. As some tree trunks had cuts and there was a pasture nearby with grazing livestock, the plot health was categorized as a 4/5.

Table 14: Data on mangroves in plot #12, sector I

Species Number Height Average Density % of Total, by of Plants (m) DBH (cm) (trees/ha) Species

Avicennia germinans 7 32 30.1 280 2

Rhizophora mangle 240 0.6 <2 9,600 79

Laguncularia racemosa 56 2 <2 2,240 19

Conocarpus erectus 0 0 0 0 0

Total 303 - - 12,120 100

As shown in Table 14, plot #12 contained 303 trees, 2% of which were black mangrove, 79% red mangrove, and 19% white mangrove. The average DBH for this plot was very low (under 2 cm), except among the black mangroves, which had an average DBH of 30.1 m. Close to this site, we identified relatively tall red mangroves, very different from the individuals previously recorded, with heights of approximately 30 m and an average DBH of 26 cm. The canopy cover was estimated to be between 0% and 25%. The density was 12,120 trees/ha. The health of this site was categorized as a 4/5. We observed positive signs of regeneration in the vicinity, including parent trees and ferns.

Table 15: Data on mangroves in plot #13, sector I

Species Number Height Average Density % of Total, by of Plants (m) DBH (cm) (trees/ha) Species

Avicennia germinans 0 0 0 0 0

Rhizophora mangle 70 4.5 6 2,800 47

Laguncularia racemosa 80 6 2.5 3,200 53

Conocarpus erectus 0 0 0 0 0

Total 150 - - 6,000 100

As shown in Table 15, plot #13 contained 150 trees, 47% of which were red mangrove and 53% white mangroves. The red mangroves’ average DBH was approximately 6 cm and their average height was 4.5 m. One exceptionally tall tree (22 m in height) was present in the plot. The overall

canopy cover was estimated to be between 75% and 100%. The density was 6,000 trees/ha. There was no sign of anthropogenic interference; thus the health of the plot was categorized as 5/5.

Table 16: Data on mangroves in plot #14, sector I

Species Number Height Average Density % of Total, by of Plants (m) DBH (cm) (trees/ha) Species

Avicennia germinans 19 8 8 760 20

Rhizophora mangle 68 12 10.5 2,720 72

Laguncularia racemosa 7 3 4 280 8

Conocarpus erectus 0 0 0 0 0

Total 94 - - 3,760 100

Plot #14 had a total of 94 trees, 72% of which were red mangroves, 8% white mangroves, and 20% black mangroves. The average DBH of the red mangroves was higher than 10 cm, while that of the black and white mangroves was 8 cm and 4 cm respectively. The density was 3,760 trees/ha and the canopy cover was estimated to be between 50% and 75%. The health of this site was 5/5.

Table 17: Data on mangroves in plot #15, sector I

Species Number of Height Average Density % of Total, by Plants (m) DBH (cm) (trees/ha) Species 0 0 0 0 0 Avicennia germinans

Rhizophora mangle 20 15 35 800 100 0 0 0 0 0 Laguncularia racemosa

Conocarpus erectus 0 0 0 0 0

Total 20 - - 800 100

As shown in Table 17, plot #15 had 20 trees, all red mangroves, with an average DBH of 35 cm. The calculated density was 800 trees/ha, and the canopy cover was estimated to be between 50% and 75%. The maximum height was 15 m. The health was categorized as 5/5.

Table 18: Data on mangroves in plot #16, sector I

Species Number Height Average Density % of Total, by of Plants (m) DBH (cm) (trees/ha) Species

Avicennia germinans 7 22 23 280 24

Rhizophora mangle 22 18 15 880 76

Laguncularia racemosa 0 0 0 0 0

Conocarpus erectus 0 0 0 0 0

Total 29 - - 1,160 100

Table 18 shows that plot #16 contained 29 trees, 24% of which were black mangrove and 76% red mangrove. The average height of black mangroves was > 22 m, and the average DBH was 19 cm. The density was 1,160 trees/ha. This site’s disturbance level was categorized at 5/5. No visible signs of pollution or human activities were observed.

Table 19: Data on mangroves in plot #17, sector I

Species Number Height Average Density % of Total, by of Plants (m) DBH (cm) (trees/ha) Species 0 0 0 0 0 Avicennia germinans

Rhizophora mangle 50 25 26 2000 91

Laguncularia racemosa 5 35 27 200 9

Conocarpus erectus 0 0 0 0 0

Total 55 - - 2200 100

As shown in Table 19, plot #17 contained 55 trees, represented by two species. The trees were 91% red mangrove and 9% white mangrove. The average height at this site, 30 m, was one of the highest recorded averages for the two species. The average DBH at the site was 26.5 cm. Canopy cover was estimated to be between 50% and 75%. The density was 2,200 trees/ha, and the health was categorized as a 4/5. Although there was no pollution and no visible signs of human activities, the site was located in a commonly used fishing area.

Table 20: Data on mangroves in plot #22, sector I

Species Number Height Average Density % of Total, by of Plants (m) DBH (cm) (trees/ha) Species

0 0 0 0 0 Avicennia germinans

Rhizophora mangle 15 30 26 600 100

Laguncularia racemosa 0 0 0 0 0

0 0 0 0 0 Conocarpus erectus

Total 15 - - 600 100

Table 20 shows that plot #22 had a total of 15 trees, all red mangroves, with an average DBH of 26 cm and average tree height of 30 m. The canopy cover was between 0% and 25%. The density was 600 trees/ha, and the plot’s health was considered 4/5. No visible signs of pollution or human activities were observed. However, many dry trunks (about 30 m in height) were seen. This situation was probably caused by aging, since only very old trees seemed to be affected. Some species of invasive grasses was also found at the site. This site may be a potential nursery area for rehabilitation activities.

Table 21: Data on mangroves in plot #23, sector I

Species Number Height Average Density % of Total, by of Plants (m) DBH (cm) (trees/ha) Species

Avicennia germinans 6 2.8 4 240 8

Rhizophora mangle 16 1.5 <2 640 22

Laguncularia racemosa 50 3.5 3 2,000 70

0 0 0 0 0 Conocarpus erectus

Total 72 - - 2,880 100

Plot #23 contained 72 trees, represented by three species. Of the total, 8% were black mangroves, 22% were red mangroves, and 70% were white mangroves. The average height of the trees was only 2.5 m, and the overall average DBH was less than 2 cm for the red mangroves. There were many white mangrove plantlets approximately 0.5 m in height across this partially flooded site. The density was 2,880 trees/ha, and the canopy cover was estimated to be between 0% and 25%. No visible signs of pollution or any other types of disturbances were identified; the health level was categorized at 5/5.

Table 22: Data on mangroves in plot #24, sector I

Species Number of Height Average Density % of Total, by Plants (m) DBH (cm) (trees/ha) Species

Avicennia germinans 6 25 20 240 13

Rhizophora mangle 22 27 22 880 49

Laguncularia racemosa 17 23 16 680 38

Conocarpus erectus 0 0 0 0 0

Total 45 - - 1,800 100

As shown in Table 22, plot #24 contained 45 trees, of which 13% were black mangroves, 49% were red mangroves, and 38% were white mangroves. The average height was 25 m and the average DBH was 19 cm. The canopy cover was estimated to be between 75% and 100%. The density was 1,800 trees/ha and the health level was 5/5.

Table 23: Data on mangroves in plot #25, sector I

Species Number Height Average Density % of Total, by of Plants (m) DBH (cm) (trees/ha) Species

Avicennia germinans 26 30 60 1,040 100

0 0 0 0 Rhizophora mangle 0

0 0 0 0 Laguncularia racemosa 0

0 0 0 0 Conocarpus erectus 0

Total 26 - - 1,040 100

Table 23 shows that plot #25 contained 26 trees, all of which were black mangroves. The average height was 30 m and the average DBH was 60 cm. The canopy cover was between 25% and 50%. The plot health was categorized as 3/5, as mangroves were being cleared in this area to create a new agricultural area.

Table 24: Data on mangroves in plot #26, sector I

Species Number Height Average Density % of Total, by of Plants (m) DBH (cm) (trees/ha) Species

0 0 0 0 0 Avicennia germinans

Rhizophora mangle 23 20 52 920 100

0 0 0 0 0 Laguncularia racemosa

Conocarpus erectus 0 0 0 0 0

Total 23 - - 920 100

Table 24 shows that plot #26 contained 23 trees, all red mangroves, with an average DBH of 52 cm and an average height of 20 m. The density was 920 trees/ha, and the canopy cover was estimated to be between 25% and 50%. The plot health was categorized as 5/5.

Table 25: Data on mangroves in plot #27, sector I

Species Number Height Average Density % of Total, by of Plants (m) DBH (cm) (trees/ha) Species

Avicennia germinans 1 20 25 40 4

Rhizophora mangle 22 15 26 880 88

Laguncularia racemosa 2 13 18 80 8

0 0 0 0 0 Conocarpus erectus

Total 25 - - 1,000 100

Plot #27 contained 25 trees, of which 88% were red mangrove, 8% were white mangrove, and 4% were black mangrove. The average height was 18 m, with the black mangroves growing above 20 m. The canopy cover was between 75% and 100%, and the average DBH was around 23 cm. The density was 1000 trees/ha. The health of the site was 5/5, as signs of natural regeneration were observed.

Table 26: Data on mangroves in plot #28, sector I

Species Number Height Average Density % of Total, by of Plants (m) DBH (cm) (trees/ha) Species

Avicennia germinans 10 10 25 400 13

Rhizophora mangle 25 0.5 <2 1,000 32

Laguncularia racemosa 42 6 4 1,680 55

0 0 0 0 0 Conocarpus erectus

Total 77 - - 3,080 100

As shown in Table 26, plot #28 contained 77 trees, 32% of which were red mangroves, 55% white mangroves, and 13% black mangroves. The average height of the red mangroves was only 0.5 m, while the black mangroves grew to an average height of 10 m. The canopy cover was between 50% and 75%, and the overall average DBH was less than 2 cm for the red mangroves, compared with 25 cm for black mangroves. The density was 3,080 trees/ha. The plot health was 5/5.

Table 27: Data on mangroves in plot #29, sector I

Species Number Height Average Density % of Total, by of Plants (m) DBH (cm) (trees/ha) Species

Avicennia germinans 0 0 0 0 0

Rhizophora mangle 26 23 43 1,040 100

Laguncularia racemosa 0 0 0 0 0

Conocarpus erectus 0 0 0 0 0

Total 26 - - 1,040 100

As shown in Table 27, plot #29 had a total of 26 trees, all red mangroves, with an average DBH of 43 cm and average height of 26 m. The density was 1,040 trees/ha, and the canopy cover was estimated to be between 75% and 100%. This site was in excellent condition, with the plot health categorized as 5/5.

Table 28: Data on mangroves in plot #30, sector I

Species Number Height Average Density % of Total, by of Plants (m) DBH (cm) (trees/ha) Species

Avicennia germinans 14 29 38 560 44

Rhizophora mangle 18 21 30 720 56

Laguncularia racemosa 0 0 0 0 0

Conocarpus erectus 0 0 0 0 0

Total 32 - - 1,280 100

Table 28 shows that plot #30 contained 32 trees, 44% of which were black mangroves and 56% of which were red mangroves. The average height of the trees was 25 m, with canopy coverage at 75% to 100%. The average DBH was 34 cm. The density was 1,280 trees/ha. There were no visible signs of pollution; therefore, the plot health was designated as a 5/5.

Sector II: Los Corozos

Four sites were surveyed around Los Corozos. The mangroves here form one continuous area, and all the trees are of similar height. The trees are in a marshy area, bordered by the sea to the east, a town to the south, and an agricultural area to the north. A majority of the forest is composed of R. mangle, occurring in fringe habitat, and only a few individuals of buttonwood mangrove were recorded at sites close to the sea. Even though the mangroves in this area seemed to be in good health, we observed a few charcoal sites near the location. Residents living around

the area indicated that mangrove wood is used locally for construction and some charcoal production. They also reported that continuous replanting efforts are occurring in the mangrove area. Some positive signs of natural regeneration were visible close to sample sites as well.

Figure 3: Satellite image of Los Corozos

Table 29: Data on mangroves in plot #18, sector II, Los Corozos

Species Number Height Average Density % of Total, by of Plants (m) DBH (cm) (trees/ha) Species

Avicennia germinans 15 15 35 600 17

Rhizophora mangle 38 6 5.5 1,520 43

Laguncularia racemosa 15 2.5 <2 600 17

Conocarpus erectus 20 4 3 800 23

Total 88 - - 3,520 100

Plot #18 contained 88 trees, representing all four species of mangroves. Of the trees, 17% were black mangroves, 43% were red mangroves, 17% were white mangroves, and 23% were buttonwood mangrove. The average height of the black mangroves was 15 m, while the other three species had an average height of 4 m. Black mangroves had an average DBH of 35 cm, while the other three species were below 10 cm. The canopy cover was estimated to be between 50% and 75%. The density was 3,520 trees/ha, and the health level was 4/5, as a grazing pasture and a road were located close to the mangrove habitat.

Table 30: Data on mangroves in plot #19, sector II

Species Number Height Average Density % of Total, by of Plants (m) DBH (cm) (trees/ha) Species

Avicennia germinans 24 4.5 2 960 17

Rhizophora mangle 30 4 2 1,200 21

Laguncularia racemosa 86 2 <2 3,440 62

Conocarpus erectus 0 0 0 0 0

Total 140 - _ 5,600 100

Table 30 shows that plot #19 contained 140 trees, including 21% red mangrove, 62% white mangrove, and 17% black mangrove. The density was 5,600 trees/ha. Mangroves in this plot grew to an average height of above 3 m and had an average DBH of 2 cm. The plot health was categorized as 4/5, as an agricultural area and a grazing pasture were located across from the mangrove habitat. The canopy cover was estimated to be between 75% and 100%.

Table 31: Data on mangroves in plot #20, sector II

Species Number Height Average Density % of Total, by of Plants (m) DBH (cm) (trees/ha) Species

Avicennia germinans 5 7 5 200 5

Rhizophora mangle 89 3 7 3,560 85

Laguncularia racemosa 10 5 2 400 10

Conocarpus erectus 0 0 0 0 0

Total 104 - - 4,160 100

Table 31 shows that plot #20 contained 104 trees, of which 5% were black mangroves, 85% red mangroves, and 7.5% white mangroves. The density was 4,160 trees/ha. The average DBH of the red mangroves was 7 cm, with an average height of 3 m. The plot health was categorized as a 3/5, as an agricultural area and an area of solid waste disposal were near the mangrove area. The canopy cover was estimated to be between 75% and 100%.

Table 32: Data on mangroves in plot #21, sector II

Species Number Height Average Density % of Total, by of Plants (m) DBH (cm) (trees/ha) Species

Avicennia germinans 1 10 60 40 2.5

Rhizophora mangle 40 7 19 1,600 95

Laguncularia racemosa 1 7 26 40 2.5

Conocarpus erectus 0 0 0 0 0

Total 42 - - 1,680 100

Plot #21 contained 42 trees, 95% of which were red mangroves, 2.5% were white mangroves, and 2.5% were black mangroves. The density was calculated at 1,680 trees/ha, while the average DBH of the plot was 35 cm. Black mangroves grew to an average of 10 m in height, while the two other species reached an average height of 7 m. The plot health was categorized as a 4/5 due to the presence of agriculture adjacent to the location and charcoal disposal sites observed nearby. The canopy cover was estimated to be between 50% and 75%.

Mapping the Mangroves

Spatial analysis for each species of mangrove was done, considering density/ha-1, height, and

DBH.

Figure 4: Density of the four mangrove species Figure 4 shows the density of the four species. R. mangle shows the highest density, with an average of 6,180 trees/ha, followed by white mangrove, with 4,106 trees/ha. The buttonwood

mangrove had the lowest density, with an average 32 tree/ha. This species was found in only two sites, one close to the beach in Bajo Yuna and the other in Los Corozos. The average density of the mangroves in Los Corozos is 3,740 trees/ha, while that in Bajo Yuna is 12,284 trees/ha.

Figure 5: Diameter at breast height (DBH) of the four mangrove species Figure 5 shows DBH intervals per species recorded within Samaná Bay. Even though the black mangrove was not the most highly represented species in the area, its average DBH (35.67 cm) was the highest, and so, by extension, was its biomass. In some areas, close to the Yuna River, some individuals had a DBH of > 60 cm. Likewise, in Los Corozos, there were a few individuals with a DBH of 60 cm.

On the muddy alluvial plains around the mouth of the Yuna River, A. germinans was the dominant species. However, many felled trees were observed across the site, either due to cutting or to natural factors such as uprooting by strong winds, possibly during the recent passage of Hurricanes Irma and Maria, and natural aging.

C. erectus was the least common species represented across the Bay. It was identified in only two places and had an average DBH of about 3.25 cm.

Figure 6: Height of the four mangrove species Figure 6 shows height intervals per species recorded within Samaná Bay. As was the case for DBH, the largest individuals were A. germinans, with a maximum height of 32 m. R. mangle had the second tallest trees, with the tallest individuals measuring > 25 m. The average height of the other two species was much lower, with L. racemosa measuring an average of 7.67 m and C. erectus measuring an average of 3.5 m.

Species Identification Based on its ecological characteristics, Samaná has historically been an important fishing area in the Dominican Republic (CEBSE, 1993). Hundreds of species are present among the coastal and marine biota of the Bay, including many crustaceans and mollusks (Herrera, 2005). In the Samaná region, marine grasses are represented by the phanerogams Thalassia testudinum and Syringodium filiforme, and in the less frequently observed Halophila decipiens and Halodule wrightii (Ferreras et al., 1990; CEBSE, 1993). These species play an important role in recycling sediment and constitute a vegetation belt that plays a key role in filtering river and runoff water. They help to form the habitat. Samaná Bay also has a wide range of birds, from water birds to mangrove and grass-shrublands birds.

Table 33: Common and scientific names of notable plants at Samaná Bay

Common Name Scientific Name

black mangrove Avicennia germinans

white mangrove Laguncularia racemosa

buttonwood mangrove Conocarpus erectus

red mangrove Rhizophora mangle

sea almond Terminalia catappa

golden leather fern Acrostichum aureum

coconut tree Cocos nucifera

common purslane Portulaca oleracea

mangrove vine Rhabdadenia biflora

In many places around mangrove habitat, patches of grass were observed, but the grass species have not been identified and do not appear in our list.

Table 34: List of birds and their conservation status (IUCN)

Common Name Scientific Name Status

white-cheeked pintail Anas bahamensis breeding resident (threatened) yellow-crowned night-heron Nyctanassa violacea breeding resident little blue heron Egretta caerulea breeding resident tricolored heron Egretta tricolor breeding resident snowy egret Egretta thula breeding resident great blue heron Ardea herodias breeding resident great egret Ardea alba breeding resident green heron Butorides virescens breeding resident white ibis Eudocimus albus breeding resident turkey vulture Cathartes aura breeding resident common moorhen Gallinula chloropus breeding resident Wilson’s snipe Gallinago delicata breeding resident Wilson’s plover Charadrius wilsonia breeding resident spotted sandpiper Actitis macularius non-breeding visitor black-necked stilt Himantopus mexicanus breeding resident sandwich tern Sterna sandvicensis breeding resident least tern Sterna antillarum breeding visitor herring gull Larus argentatus non-breeding visitor laughing gull Larus atricilla breeding resident common ground dove Columbina passerina breeding resident scaly-napped pigeon Patagioenas squamosa breeding resident white-crowned pigeon Patagioenas leucocephala breeding resident Hispaniolan lizard-cuckoo Coccyzus longirostris endemic smooth-billed ani Crotophaga ani breeding resident

belted kingfisher Ceryle alcyon non-breeding visitor Hispaniolan woodpecker Melanerpes striatus endemic northern mockingbird Mimus polyglotos breeding resident American redstart Setophaga ruticilla non-breeding visitor Greater Antillan grackle Quiscalus niger breeding resident magnificent frigatebird Fregata magnificens breeding resident

Table 35: Common and scientific names of crustaceans and mollusks identified

Common Name Scientific Name

Crabs

Fiddler crab Uca sp.

Mangrove crab Aratus pisonii

Mollusks/Crustaceans

Mangrove oyster Crassostrea rhizophorae

Pearl oyster Pinctada sp.

Southern White shrimp Penaeus schmitti

The species of crustaceans and mollusks listed in Table 35 have been identified all over the Bay. However, other associate species have been observed in other places inside the Park, such as white shrimp, a key species that represents around 86% (Sang et al., 1997) of the total shrimps captured. Fiddler crabs are also bioindicators of the overall quality of the mangrove habitat. Other crustaceans and fish in the area include but not limited to Callinectes sapidus, some Gerridae species (fish; the common name is mojarra), and Clupeidae (herrings).

Water Quality Assessment

Water quality assessments were performed within the same subdivisions of the area as was done in the mangrove survey, measuring pH, salinity, and temperature. Temperature data were difficult to accurately and consistently measure, as surveys were done at different times of the day. Temperature readings fluctuated at the sites between 24°C and 32°C.

In Samaná Bay, the average salinity ranged between 0.5 and 25 ppt. At the riverine edge and fringing area of the Yuna River, the salinity readings were quite low, ranging between 0.5 and 4 ppt, and at the site near the Barracote River, the salinity ranged from 0.5 to 10 ppt. In the zones between both rivers, the salinity was closer to the average salinity observed in open water, ranging between 18 and 25 ppt. Salinity readings taken around this time period may have been lower than normal, due to an inflow of freshwater runoff in the Bay after the passage of Hurricanes Irma and Maria, which caused flooding. The pH in Samaná Bay and Los Corozos ranged from 7.2 to 8.5.

Discussion and Recommendations

Overall, the mangroves in Samaná Bay seem to be relatively healthy. There is some evidence of anthropogenic activities, such as fishing, agriculture, and harvesting of wood within the mangrove forest. However, these activities seem to be limited and have not significantly affected the mangrove area. It is important to note that fishing occurs in communities near Samaná Bay. Fishers are aware of the importance of this particular ecosystem for their activities.

The mangroves themselves are not severely threatened by human activities, though evidence of wood harvesting and downed wood (dead wood on the forest floor) was observed at different sites. The downed wood that was observed seemed to be naturally occurring, due to parts of the trees breaking off or dying from age, or to strong winds passing through the area. Category 5 storms had recently passed over the northeastern portion of the DR.

Within the same area, there was evidence of self-regeneration, as many plantlets were observed at specific sites. L. racemosa plantlets occurred at the highest densities around the alluvial fan at the mouth of the Yuna and Barracote Rivers. Close to these sites were grazing pastures for livestock, containing cattle. If left unchecked or unmanaged, this sort of agricultural activity has the potential to interfere with the integrity of the mangrove system. Therefore, it is recommended that biodiversity conservation efforts are implemented at these sites to protect them. According to locals, some areas close to the mangroves have been identified by certain farmers as potential or future agricultural zones, due to the productivity of the soil. They spoke of plans to create new access points into the mangroves and to drain the marsh water in many places. If implemented, these plans could have detrimental impacts on the mangroves. Action should be taken to document and meet the primary needs of locals in the area so that they will no longer need to alter the mangrove ecosystem for economic gain.

The mangroves around the Barracote River presented the same regeneration profile as for the Yuna River, with many plantlets at the edge of the River. Only minimal restoration activities (if any) are required at these sites. Evidence of natural regeneration was also observed at sites in Los Corozos. However, this is a much smaller area, flanked by agricultural activities in the north, a settlement in the south, and a road in the east. Therefore, it is recommended that protection, restoration, and awareness activities be continued by the local NGOs and community groups to ensure the health and integrity of the ecosystem.

Mangroves in Samaná Bay offer a large range of ecosystem services. They serve as fish nurseries and habitat, aid in coastal protection, and filter water to improve the quality of water flowing from the land into the ocean. Mangroves also play a vital role in the interconnected nature of coastal ecosystems, along with coral reefs and sea grasses, which provide joint benefits to human populations. The mangrove forests of Samaná Bay are threatened mainly by

- Solid waste pollution (locals dump garbage in the mangroves, and there is a municipal dump for Sanchez, to the north of the mangrove forest), - Water pollution, due to excrement and chemicals from agricultural areas and livestock nearby, and

- Land conversion for agriculture and aquaculture activities.

At many sites in Bajo Yuna, there were signs of solid waste pollution, mostly in the sites located near beaches. Tourism and the settlements around Samaná have had an indirect negative impact on the ecosystem. Continued support is needed for solid waste management programs, and ongoing awareness activities are key in galvanizing community support for conservation programs.

Various crab species, such as A. pisonii and Uca sp., were observed at inundated fringe sites where R. mangle was present. Mangrove crabs are useful bioindicators of the quality of mangrove habitats, as they are ecologically important organisms in mangrove environments. The partially immersed roots of R. mangle are meso-ecosystems that provide habitats for abundant mangrove and pearl oysters, as well as many sponges and tunicates. The planktonic and benthic animal communities (especially filter feeders) play very important roles in mangrove ecosystems, filtering pollutants and sediment that could otherwise cause algal blooms. These filter feeders and other associated organisms are also food for birds, fish, and mammals that live among the roots of the four mangrove species observed. The juveniles of a wide variety of marine organisms are found in, or close to, the dense network of prop roots of R. mangle, which provide shelter and function as a natural nursery ground. Some of these species are of commercial importance for Samaná Bay, such as certain species of shrimp.

Conclusion

The mangroves in Samaná Bay seem relatively healthy with positive signs of self-regeneration in several areas around the Barracote and Yuna Rivers. The mangrove forest is not severely threatened, but in many places there are visible signs of pollution that require immediate correction. Waste management programs should be continued and expanded within the Bay.

Bajo Yuna National Park is a good potential site for restoration and conservation programs, and can also support ecotourism opportunities. However, any ecotourism activities will have to be in line with the conservation objectives of the various stakeholders.

Literature Cited

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Desse, M., 2002. Pression anthropique et dégradation des littoraux haïtiens : l'exemple du golfe de la Gônave, Les Cahiers d’Outre-Mer, 219.

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Ferreras, J., Lysenko, N., and Domínguez, T.G., 1990. Proyecto inventario de los recursos naturales de la Bahía de Samaná. Informe final al Centro de Conservación Marina. Centro de Investigaciones de Biología Marina, CIBIMA, 51 pp.

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Annexes

Annex 1: Crab in Samaná Bay (Uca sp.)

Annex 2: Crab in Samaná Bay (Aratus pisonii)

Annex 3: Birds around Rio Barracote

Annex 4: Birds: Fregata magnificens

Annex 5: Mangrove plantlets around Rio Barracote

Annex 6: Fishers in Samaná Bay around Rio Yuna

Annex 7: Solid waste (bottles and other trash) under some red mangrove trees

Annex 8: Solid waste on the beach in front of the mangrove area in Bayo Yuna

Annex 9: Rhabdadenia biflora

Annex 10: Mangrove oyster

Annex 11: Charcoal production near the mangroves in Los Corozos

Annex 12: View from the mangrove area in Los Corozos

Annex 13: View of the mangrove area near Sanchez

Annex 14: Pasture near the mangrove

Annex 15: Mangrove around Rio Barracote