Biodiversity Data Journal :
Research Article
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Corresponding author: Gorky Ríos-Alvear (gork_dan@hotmail.com)
Academic editor: Ricardo Moratelli
Received: 28 Nov 2022 | Accepted: 14 Feb 2023 | Published: 27 Feb 2023
© 2023 Juan Reyes-Puig, Carolina Reyes-Puig, Jessica Pacheco-Esquivel, Santiago Recalde, Fausto Recalde, Darwin Recalde, Jordy Salazar, Eduardo Peña, Silvia Paredes, Marina Robalino, Fernanda Flores, Vladimir Paredes, Edelina Sailema, Gorky Ríos-Alvear
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Reyes-Puig JP, Reyes-Puig C, Pacheco-Esquivel J, Recalde S, Recalde F, Recalde D, Salazar J, Peña E, Paredes S, Robalino M, Flores F, Paredes V, Sailema E, Ríos-Alvear G (2023) First insights in terrestrial mammals monitoring in the Candelaria and Machay Reserves in the Ecuadorian Tropical Andes. Biodiversity Data Journal 11: e98119. https://doi.org/10.3897/BDJ.11.e98119
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Habitat disturbance leads to biodiversity decline and modifications in the landscape structure and composition, affecting both dispersal movements and ecological processes at different temporal and spatial scales. The Ecuadorian Tropical Andes harbour suitable habitats for the distribution of a wide variety of species; however, there is a lack of studies focused on mammal diversity and its association with the habitat attributes in the central-eastern slopes. Here, we reported the diversity of terrestrial mammals recorded between 2019 and 2021 in a camera-trap monitoring study in the Candelaria and Machay reserves in the upper basin of the Pastaza River, Ecuador. We performed site-occupancy probability analysis to assess the influence of spatial variables in the species’ occurrence and also, based on natural marks, we reported preliminary findings in Andean bear individual identification. We detected 22 species of terrestrial mammals. Alpha diversity was similar between reserves with slightly higher species richness in Machay. Evenness indices showed unequal species distribution, with the Andean bear and domestic dogs exhibiting greater dominance. In addition, species composition was dissimilar between reserves, where the species turnover mostly explained the beta diversity. We observed that Andean bear and puma detections increased according to the natural vegetation cover. Conversely, domestic dogs were frequently detected in cells with an increasing proportion of pastures and crops. Additionally, we identified 26 Andean bears and six individuals recaptured during our study. Our results caution about the disturbance derived from human activities since we recorded unprecedented detections of domestic dogs in wild habitats. Nonetheless, it highlights the importance of private conservation areas (e.g. Candelaria, Machay and others) for supporting the occurrence and dispersal of terrestrial mammal species between larger areas in the upper basin of the Pastaza River.
ecological corridors, CELS, landscape ecology, mammal diversity, photo identification
The main causes for the global biodiversity decline include forest clearing, natural resources overexploitation, habitat change, invasive alien species, hunting, climate change, fires and pollution (
The tropical Andes are biodiversity hotspots critical for the provision of ecosystem services (
In this paper, we present the first results of a two-year pilot camera-trap monitoring study of medium- and large-sized mammals in which we identified the richness and diversity of species of two reserves located in the east-central Andes of Ecuador (Machay and Candelaria), in the upper basin of the Pastaza River. In addition, we estimated the occupancy and detection probability of this group and its association with spatial variables and finally we took advantage of the methodology to recognise unique individuals of spectacled bears that allow us to warn about the importance of the region for habitat connectivity, conservation and management of landscape species.
We conducted the study in the eastern slopes of the Andes in Ecuador, in the Cerro Candelaria and Machay Reserves of the Fundación Ecominga (Fig.
We conducted a camera-trap survey consisting of four sampling campaigns, from late 2019 to 2021. We defined 15 cells of 1 km2 at each Reserve. Each sampling cell was surveyed twice a year with one camera trap active during the dry and rainy seasons. Effective sampling days varied from 12 - 65 due to the camera’s performance and the lockdown and mobility restrictions caused by the COVID-19 pandemic outbreak (Table
Sampling campaign |
Date |
Active cameras |
Effective sampling days Mean (± SD) |
|||
Start |
End |
Cerro Candelaria |
Machay |
Cerro Candelaria |
Machay |
|
F1 |
December 2019 |
April 2020 |
12 |
9 |
58.66 (± 37.7) |
58.3 (± 60) |
F2 |
October 2020 |
December 2020 |
14 |
12 |
49 (± 17.4) |
36.2 (± 25.2) |
F3 |
April 2021 |
July 2021 |
9 |
9 |
34.1 (± 34.8) |
36.6 (± 33.7) |
F4 |
August 2021 |
October 2021 |
14 |
11 |
45.87(± 29) |
46.1(± 31.8) |
We computed the species relative abundance, based on the average number of independent camera trap records during 100 trap-nights in each Reserve during our study (
We estimated alpha and beta diversity for each Reserve. Diversity analyses were conducted following the Hill numbers approach (i.e. the effective number of species) (
We modelled the site-occupancy probability, defined as the proportion of habitat occupied by a particular species under the assumptions of closed population within, but not between seasons, sampling independence and equal probability of occupancy and detection across sampling sites and surveys (
Hypothesis for site-occupancy probability estimates. ψ (Occupancy probability) and p (Detection probability) ɣ (Colonisation probability), ε (extinction probability). For j = sites, i = species and Kj = surveys at each site.
Variable |
Model |
Description |
Conceptual model |
Vegetation (Veg) |
logit (ψi)= β0 + mean Vegj |
Proportion of vegetation within the 1 km2 sampling cell and at 250 m buffer surrounding each camera trap. We defined three classes: 1. Natural vegetation 2. Pastures and crops 3. Areas without vegetation. |
1. The occupancy of wildlife species increases at high proportions of natural vegetation. 2. The occupancy of wildlife species increases at low proportions of pastures and crops. 3. The occupancy increases at low proportions of areas without vegetation. |
Distance to Protected Areas (PAdist) |
logit (ψi)= β0 + PAdistj |
The nearest Euclidean distance from the camera trap to the border of the protected areas. |
The occupancy of wildlife species increases closer to the protected areas. |
Distance to creeks (Cdist) |
logit (ψi)= β0 + Cj |
The nearest Euclidean distance from the camera trap to creeks. |
The occupancy of wildlife species increases closer to creeks as they provide natural corridors for dispersal. |
Distance to roads (Rdist) |
logit (ψi)= β0 + Rdistj |
The nearest Euclidean distance from the camera trap to roads. |
The occupancy of wildlife species increases at a high distance from roads. |
Human accessibility (Acces) |
logit (ψi)= β0 + Accesj |
Probability of human access to a pixel as a function of the existence of roads, vicinity to human settlements and navigable rivers ( |
The occupancy probability increases at a low probability of human accessibility. |
Rugosity (Rugos) |
logit (ψi)= β0 + Rugosj logit (ψi)= α0 + Rugosj |
Raster obtained from the MODIS satellite computed as a function of elevation, shape and topographic slope. |
The occupancy probability increases at high levels of rugosity as a proxy of less disturbed areas. The detection probability decreases as rugosity increases. |
Forest loss (Floss) |
logit (ψi)= β0 + Flossj |
Rate of tree canopy removal from 2000 - 2018 ( |
The occupancy probability is higher in areas with low rates of forest loss. |
Forest gain (Fgain) |
logit (ψi)= β0 + Fgainj |
The establishment of tree canopy from a non-forest state from 2000 – 2012 ( |
The occupancy probability increases in areas with high rates of forest gain. |
Ecological integrity index (EII) |
logit (ψi)= β0 + EIIj |
Forest condition determined by the degree of human pressures and loss of habitat connectivity ( |
The occupancy probability increases in areas with high ecological integrity. |
Rain seasonality (Rain) |
logit (ɣi)= β0 + Rainj logit (εi)= β0+ Rainj |
Indicator variable to reflect the rain regime during the sampling campaign ( |
The occupancy changes between sampling seasons according to the rain regime. |
Occurrence of domestic dogs (Dogs) |
logit (ψi)= β0 + Dogsj logit (ψi)= α0 + Dogsj logit (ɣi)= β0+ Dogsj logit (εi)= β0 + Dogsj |
Occurrence of domestic dogs recorded by the camera traps during the sampling campaign |
The occupancy and detection probabilities are higher in areas where domestic dogs are absent. The occurrence of domestic dogs leads to changes in occupancy between seasons. |
Sampling effort (eff) |
logit (zi p) = α0 + eff Kj) |
Effective sampling days of the camera traps |
Detection probability increases as more sampling effort devoted. |
We assessed the spatial arrangement of detections according to the spatial features within the study area to identify potential characteristics influencing the occurrence of the modelled species. We applied the Wilcoxon-Mann-Whitney test to assess the differences between detections and non-detections within the study area and summarised the results through the “ggstatsplot” R package (
We performed a photo identification only for Andean bears, based on their facial marks (
We documented 284 independent camera-trap records of medium and large-size terrestrial mammals in 2814 sampling days at the Candelaria Reserve and 218 records in 2658 sampling days at the Machay Reserve. Species’ relative abundance ranged from 0.03 to 3.13 camera records per 100 sampling days (Table
Photographic rate of the species recorded in the camera trapping monitoring at the Candelaria and Machay Reserves during 2019 – 2021. We compared our findings with a previous study in the Llanganates National Park.
Relative abundance (± 90% CI) |
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Our study |
Palacios et al. (2018) |
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Order |
Family |
Species |
Candelaria |
Machay |
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Artiodactyla |
Cervidae |
Mazama rufina |
0.33 (0.38) |
0.62 (0.95) |
0.82 (0.81) |
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Pudu mephistophiles |
0.16 (0.25) |
0.69 (0.70) |
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Tayassuidae |
Tayassu pecari |
0.04 (0.09) |
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Didelphimorphia |
Didelphidae |
Didelphis albiventris |
0.3 (0.7) |
0.1 (0.23) |
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Didelphis pernigra |
0.15 (0.28) |
0.46 (0.4) |
0.39 (0.35) |
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Carnivora |
Canidae |
Canis familiaris |
1.42 (1.61) |
0.76 (0.6) |
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Felidae |
Leopardus tigrinus |
0.76 (0.77) |
0.68 (0.43) |
0.30 (0.26) |
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Puma concolor |
0.8 (0.43) |
0.99 (1.2) |
0.65 (0.35) |
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Mustelidae |
Eira barbara |
0.33 (0.3) |
0.37 (0.33) |
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Mustela frenata |
0.03 (0.08) |
0.17 (0.41) |
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Procyonidae |
Nasua nasua |
0.27 (0.27) |
0.74 (0.26) |
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Nasua olivacea |
0.24 (0.46) |
0.07 (0.1) |
0.26 (0.22) |
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Ursidae |
Tremarctos ornatus |
3.13 (1.58) |
2.32 (3.24) |
0.86 (0.48) |
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Perissodactyla |
Tapiridae |
Tapirus pinchaque |
0.4 (0.68) |
1.64 (1.22) |
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Pilosa |
Myrmecophagidae |
Tamandua tetradactyla |
0.3 (0.36) |
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Primates |
Cebidae |
Cebus yuracus |
0.03 (0.06) |
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Rodentia |
Cuniculidae |
Cuniculus paca |
0.04 (0.09) |
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Cuniculus taczanowskii |
0.1 (0.25) |
0.34 (0.28) |
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Dasyproctidae |
Dasyprocta fuliginosa |
0.67 (0.71) |
0.4 (0.56) |
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Leporidae |
Sylvilagus andinus |
0.07 (0.16) |
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Sciuridae |
Microsciurus flaviventer |
0.41 (0.97) |
0.03 (0.08) |
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Syntheosciurus granatensis |
0.05 (0.06) |
0.44 (0.88) |
We detected a total of 22 species of terrestrial mammals in 502 independent camera-trap records. We recorded 17 species at the Candelaria and 19 at the Machay Reserve. Alpha diversity appears to be similar between Reserves with a slight increase in the number of species in Machay (Table
Summary of medium- and large-size mammal’s diversity indices and Hill numbers. H0: species richness, H1: Shannon-Wiener exponential, H2: the reciprocal of Simpson and H3: Berger-Parker index, J: Pielou’s index, E: Simpson's index.
Index |
Candelaria |
Machay |
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F1 |
F2 |
F3 |
F4 |
Total |
F1 |
F2 |
F3 |
F4 |
Total |
|
H0 (S) |
13 |
12 |
7 |
12 |
17 |
13 |
11 |
14 |
12 |
19 |
H1 (exp H') |
8.62 |
9.23 |
3.65 |
4.76 |
10.15 |
6.34 |
6.04 |
10.69 |
10.31 |
11.31 |
H2 (1/D)) |
6.12 |
7.76 |
2.47 |
2.86 |
7.28 |
3.91 |
3.88 |
8.69 |
9.29 |
8.40 |
H3 (d) |
4.85 |
6.93 |
2.09 |
2.37 |
5.90 |
3.14 |
3.15 |
7.63 |
7.61 |
6.90 |
J |
0.83 |
0.89 |
0.67 |
0.63 |
0.82 |
0.72 |
0.74 |
0.89 |
0.94 |
0.82 |
E |
0.47 |
0.65 |
0.35 |
0.24 |
0.43 |
0.30 |
0.35 |
0.62 |
0.77 |
0.44 |
Smith & Wilson index |
0.60 |
0.65 |
0.76 |
0.42 |
0.40 |
0.64 |
0.61 |
0.69 |
0.71 |
0.40 |
The estimated diversity for Candelaria and Machay communities through rarefaction and extrapolation curves indicated the same trend showed by alpha diversity, identifying Machay as the more diverse locality (Fig.
Diversity estimators of medium- and large-size mammals in the Candelaria and Machay Reserves. Obs: Observed species richness, S1: singletones, S2: doubletones, Jack1ab: first order Jackknife, Jack2ab: second-order Jackknife, Chao 1: Chao estimator based on abundance and their bias-corrected complements (Jack1abp, Jack2abp, Chao1P).
Obs |
S1 |
S2 |
Jack1ab |
Jack1abp |
Jack2ab |
Jack2abp |
Chao1 |
Chao1P |
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Candelaria |
F1 |
13 |
2 |
0 |
15 |
15.36 |
17 |
17.4 |
14 |
14.33 |
F2 |
12 |
2 |
1 |
14 |
14.39 |
15 |
15.42 |
12.5 |
12.85 |
|
F3 |
7 |
3 |
1 |
10 |
11.84 |
12 |
14.2 |
8.5 |
10.06 |
|
F4 |
12 |
7 |
1 |
19 |
25.47 |
25 |
33.51 |
22.5 |
30.16 |
|
Machay |
F1 |
13 |
3 |
3 |
16 |
16.85 |
16 |
16.85 |
13.75 |
14.48 |
F2 |
11 |
7 |
1 |
18 |
25.29 |
24 |
33.72 |
21.5 |
30.21 |
|
F3 |
14 |
7 |
2 |
21 |
26.25 |
26 |
32.5 |
21 |
26.25 |
|
F4 |
12 |
1 |
1 |
13 |
13.09 |
13 |
13.09 |
12 |
12.08 |
Rarefaction (solid lines) and extrapolation (dashed lines) curves for the medium- and large-size mammal communities in the Candelaria and Machay Reserves. A Estimated species diversity according to the sampling units; B Estimated sample coverage according to the sampling units; C Estimated species diversity according to the sample coverage.
We estimated the occupancy probability for the Andean bear, puma, oncilla and domestic dogs since they exhibited the highest number of detections recorded during the study (Fig.
Average occupancy (ψ) and detection probabilities (p), based on the null models (ψ(.)p(.)) for the Andean bear, puma, oncilla and dogs in the Candelaria and Machay Reserves.
Delta AIC |
ψ (± SE) |
p (± SE) |
|
Andean bear |
4.59 |
0.6 (0.1) |
0.27 (0.06) |
Puma |
3.34 |
0.4 (0.1) |
0.17 (0.08) |
Oncilla |
0 |
0.33 (0.1) |
0.1 (0.08) |
Domestic dogs |
0 |
0.2 (0.1) |
0.22 (0.2) |
According to the camera traps placement, we observed that 78%, 93% and 74% of Andean bear detections were significantly more frequent in cells with a high proportion of natural vegetation, at very low levels of vegetation absence at a 1 km2 scale and in areas with low levels of rugosity, respectively (rugosity index range = 1.05-1.3) (Fig.
Arrangement of detections of Andean bears according to the spatial variables in the Candelaria and Machay Reserves. A Detections according to the percentage of natural vegetation at 1 km2; B Detections according to the percentage of the area without vegetation at 1 km2; C Detections according to the rugosity index.
Arrangement of detections of Pumas according to the spatial variables in the Candelaria and Machay Reserves. A Detections according to the percentage of natural vegetation at 1 km2; B Detections according to the percentage of natural vegetation at 250 m buffer; C Detections according to the percentage of the area without vegetation at 1 km2; D Detections according to the percentage of the area without vegetation at 250 m buffer.
We reviewed 756 camera-trap records of Andean bears collected during the study, 72.5% of which correspond to the Candelaria Reserve and 27.5% to the Machay Reserve, comprising 135 independent records. We identified at least 26 Andean bears during the study, 15 in the Candelaria and 11 in the Machay Reserve (Figs
The Andes of Ecuador, Peru and Bolivia are amongst the areas with the highest diversity and endemism of terrestrial mammals in the Neotropics (
The number of detections conditioned the species occupancy estimation since four of the 22 species documented contained 53% of the total detections during the study, while the 18 species remaining contributed between 0.2 and 6.6% of detections individually (Fig.
The number of Andean bears identified in our study exceeds that documented by
Our study highlights the importance of the Candelaria and Machay Reserves as highly diverse areas encroaching in a human-dominated landscape. We expect our results serve as a starting point for establishing a participative landscape scale monitoring network promoting the involvement of conservationists and private stakeholders in CELS. We expect our results to contribute to strengthening the management capacity in the Llanganates and Sangay National Parks, allowing park managers to capitalise on conservation outcomes through coordinated work with local conservationists. In addition, we expect local governments to take advantage of our information to make informed decisions regarding the land-use change and management taking into account the importance of private reserves for strenghthening the habitat connectivity and supporting the endeavour of local conservationists within CELS.
We thank WWF Ecuador for supporting our fieldwork campaigns and the Asociación de Turismo Comunitario Quinde Warmi and Rolando Peña for their support and assistance during the fieldwork. We thank Lou Jost, Heitor Bissoli-Silva and one anonymous reviewer for their valuable comments and suggestions to improve the manuscript. We thank World Land Trust, Rainforest Trust, Puro Coffee, Naturetrek and the Orchid Conservation Alliance for their help in the conservation of Fundacion EcoMinga's reserves in CELS. We highlight our partners' conservation efforts in CELS since their commitment makes this labour possible. This research was supported by Universidad San Francisco de Quito USFQ, Museo de Zoología & Laboratorio de Zoología Terrestre and Instituto iBIOTROP. CRP work is supported by COCIBA grants (HUBI ID: 12267), USFQ. We thank the Ministry of Environment of Ecuador for the framework agreement MAE-DNB-CM-2018-0106-USFQ.
Accumulated beta diversity considering the beta diversity partitioning approach.