550 V. H. Luja et al.
TABLE 2 Land-cover change during 1999–2019 in the study area. 1999
Land cover
Agricultural land Bare land Mangrove
Infrastructure Water bodies
Secondary vegetation 117.67
2,065.31 58.83
1,017.44 376.67
39 2
2019
Area (ha) % of total area Area (ha) % of total area 2,331.34
2,881.36 65.96
35 1
17 6
1,510.12 262.59 827.17 266.83
50 1
26 5
14 5
−555.19 203.76
−190.27 −109.84
Change (ha) 550.02 −51.71
Annual change rate (ha/year)
−27.760 10.188
27.501 −2.586
−9.514 −5.492
TABLE 3 Transition matrix (area in ha) of land-cover changes between 1999 and 2019. Note that some land-cover change involved marine areas, which are not included here as these were not relevant for our analysis.
Land-cover type in 2019
Land-cover type in 1999 Water bodies Infrastructure Mangrove Agricultural land Bare land Secondary vegetation Water bodies
Infrastructure Mangrove
Agricultural land Bare land
Secondary vegetation
666.86 0.04
118.06 32.15 5.94 3.29
0.66
57.66 58.99 53.67 11.45 78.80
160.37 0.02
1,283.83 47.56 9.43 7.33
2020 = 13), with a naïve occupancy of 0.84. Relative abun- dance index was 4.95 independent records/100 camera-trap days in 2019 and 5.36 in 2020. For 2019 the estimated popu- lation was 6–10 individuals (SE = 0.92,CI = 95%) under the model that best fit the data (Mth; population estimate under temporal variation and individual heterogeneity in the capture probabilities), and for 2020 itwas six individuals (SE = 0.18,CI = 95%) under the model M0 (the probability of capture is the same for all individuals and is not influ- enced by environment, time or response of individuals). Half of the mean maximum distance moved was 3 km, and the effective trapping area was 111.57 km2. Mean jaguar density (D) was 5.3 ± SE 0.92 individuals/100 km2 in 2019, and 5.3 ± SE 0.18 individuals/100 km2 in 2020.
Relative abundance of potential prey
Of all species recorded during this study, 14 (11 mammals, two birds, one reptile) have been reported as potential prey of the jaguar in scientific literature. The relative abun- dance index during both survey periods was highest for the domestic cattle Bos taurus (2019 = 19.03; 2020 = 20.69 independent records/100 camera-trap days), followed by the Mexican cottontail Sylvilagus cunicularius (2019 = 16.69; 2020 = 6.91 independent records/100 camera-trap days) and white-tailed deer Odocoileus virginianus (2019 = 4.80; 2020 = 4.12 independent records/100 camera-trap days; Table 1).
109.79 0.92
285.07
2,168.10 60.56
229.96 Land-cover changes
The image interpretation precision test returned a value of 81.89%, with a concordance measure (kappa value) of 82.17 (see matrices in Supplementary Material 1). In 1999, agricul- tural land covered 39%(2,331 ha) of the study area, followed by mangroves with 35%(2,065 ha). In 2019, agricultural land had increased to 2,881 ha (50% of the study area) and man- groves decreased to 1,510 ha (26%of the study area; Table 2). With the transition matrix, which shows the change in the area covered by each land-cover type between 1999 and 2019, we determined that 1,283 ha of mangroves remained un- changed over this 20-year period, but 285 ha were replaced by agricultural land (Table 3).
Discussion
We found that a resident jaguar subpopulation comprising five adult females, two adult males and one cub persists in the study area. Population density is high (5.3 individuals/ 100 km2), supported by at least 14 wild prey species, and des- pite the fact that natural habitat is rapidly being modified, with agricultural lands and shrimp farms replacing man- groves (agricultural land increased from 39 to 50% of the study area, and mangroves decreased from 35 to 26%of the study area during 1999–2019). Previous studies have documented that jaguar distribution is highly associated with availability of natural habitat and low levels of an- thropogenic disturbance (Jędrzejewski et al., 2018), and
Oryx, 2022, 56(4), 546–554 © The Author(s), 2022. Published by Cambridge University Press on behalf of Fauna & Flora International doi:10.1017/S0030605321001617
19.56 0.00
19.17 0.02
27.19 0.00
18.55 0.00
163.26 25.33 2.75
56.70
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84 |
Page 85 |
Page 86 |
Page 87 |
Page 88 |
Page 89 |
Page 90 |
Page 91 |
Page 92 |
Page 93 |
Page 94 |
Page 95 |
Page 96 |
Page 97 |
Page 98 |
Page 99 |
Page 100 |
Page 101 |
Page 102 |
Page 103 |
Page 104 |
Page 105 |
Page 106 |
Page 107 |
Page 108 |
Page 109 |
Page 110 |
Page 111 |
Page 112 |
Page 113 |
Page 114 |
Page 115 |
Page 116 |
Page 117 |
Page 118 |
Page 119 |
Page 120 |
Page 121 |
Page 122 |
Page 123 |
Page 124 |
Page 125 |
Page 126 |
Page 127 |
Page 128 |
Page 129 |
Page 130 |
Page 131 |
Page 132 |
Page 133 |
Page 134 |
Page 135 |
Page 136 |
Page 137 |
Page 138 |
Page 139 |
Page 140 |
Page 141 |
Page 142 |
Page 143 |
Page 144 |
Page 145 |
Page 146 |
Page 147 |
Page 148 |
Page 149 |
Page 150 |
Page 151 |
Page 152 |
Page 153 |
Page 154 |
Page 155 |
Page 156 |
Page 157 |
Page 158 |
Page 159 |
Page 160 |
Page 161 |
Page 162 |
Page 163 |
Page 164