Marcos Coutinho

Distribuição e quantificação de classes de vegetação do Pantanal através de levantamento aéreo

An aerial survey was adapted and used for the first time to elaborate maps of distribution and quantification of vegetation classes in the Pantanal wetland, per sub-region. Sixteen vegetation classes where identified based on phytophysiognomic aspects, the most important being grassland (31.1%), cerradao woodland (22.1%), cerrado (14.3%), marshes (7.4 %), semideciduous forest (4.0%), gallery forest (2.4%) and floating mats (2.4%). These informations can support decisions in the conservation or selection of preserved areas, as well as to help to monitor vegetation over a vast and remote region.

Aerial surveys of caiman, marsh deer and pampas deer in the Pantanal Wetland of Brazil

The yacare caiman (Caiman c. yacare) was illegally hunted in the Pantanal during the 1970s and 1980s at levels that may have reached one million skins per year. The possibility that yacare caiman had been over-exploited generated pressure for a monitoring programme for caiman populations. The marsh deer (Blastocerus dichotomus) and pampas deer (Ozotocerus bezoarticus) are listed as endangered in Brazil and need the protection of effective management programmes. Ground surveys are difficult for the extensive and inaccessible Pantanal Wetland, south-western Brazil, but aerial surveys provided information that allowed re-evaluation of conservation priorities. Caiman and marsh deer have larger populations than was believed. Preliminary data indicates that the pampas deer density decreased at a rate of about 30% per year from 1991 to 1993. This indicates the need for detailed ground-level studies for the pampas deer population in the Pantanal. We recommend a long term monitoring program using standardized counting procedures for wildlife populations in the Pantanal.

EFFECT OF HABITAT AND SEASONALITY ON THE DENSITIES OF CAIMAN IN SOUTHERN PANTANAL, BRAZIL

Studies of variation in the population densities of animals are of importance for at least two major reasons: (i) understanding the factors responsible for such variation contributes to general theory of population dynamics (Connell & Souza 1983, McArddle et al. 1990, Pimm & Redfearn 1988, Taylor 1961), and (ii) they provide basic data for management decisions relative to population exploitation or conservation (Caughley 1977, Clark 1976, May 1976). The yacare caiman (Caiman crocodilusyacare) was subject to illegal harvesting during the last three decades and was possibly the most exploited crocodilian in the world (Crawshaw 1987). More recently, legal exploitation of natural populations of yacare caimans has been permitted through a ranching system where eggs are collected in the wild and hatchlings are raised in captivity for commercial purposes. Another potential strategy for managing natural populations of caimans in the Pantanal is to establish a sustained yield-harvesting programme of larger caiman, which may be effective in promoting habitat conservation. However, in both cases accurate and precise methods to estimate populations size and/or trends are required to evaluate impacts (Webb & Smith 1987). Spotlight surveys have been widely used to monitor crocodilian populations and are precise and accurate in some habitats (Chabreck 1966, Glastra 1983). In the Pantanal, spotlight surveys have been of limited use because: (i) reaching remote areas by boat is logistically difficult; (ii) the wetlands are heavily vegetated such that crocodiles are difficult to see at night (Campos et al. 1995); and

Terrestrial Activity of Caiman in the Pantanal, Brazil

Abstract Coordinated terrestrial movement has not previously been reported in crocodilians. However, between 1989 and 1999, 94% of 525 Caiman crocodilus yacare found on land in the Pantanal were in coordinated groups (n = 73) walking head to tail and forming nearly straight lines. Caimans left pools and initiated terrestrial movements spontaneously and in response to disturbance by researchers and hunters. The sex ratio of the groups was biased toward males (0.8 ± 0.24) and was similar to that found in aquatic habitats in the study area. However, two groups consisted only of females. When caimans left pools subjected to disturbances, such as hunting and capture for research, they walked head to tail in lines. Caimans that left pools in response to disturbance buried in mud near pools or in leaf litter in forest.

Hepatozoon caimani (Apicomplexa: Hepatozoidae) in Wild Caiman, Caiman yacare, from the Pantanal Region, Brazil

Abstract The prevalence and parasitemia of Hepatozoon caimani in the natural population of the caiman, Caiman yacare, from the Pantanal area, state of Mato Grosso do Sul, central Brazil, were evaluated according to gender and month of capture from July 2006 to February 2008. Blood samples were obtained bimonthly from a total of 229 caimans, and 76% were positive. Prevalence varied significantly according to sampling month and animal size. Almost all adults (100%) and young-adults (97%) were positive, while 63% of juvenile caimans were positive and all of the youngest individuals were negative. These results indicate that caimans are infected for the first time as juveniles. The mean parasitemia in blood was 13.5 ± 13.0 (n  =  174; 1–96 parasites) and did not significantly vary with respect to gender, month of sampling, size, or weight of the caiman. The frequency distribution of parasites in the caiman population was aggregated. Differences in feeding habits and exposure to vectors between the youngest caimans and juveniles are hypothesized as the main risk factors for caimans to acquire H. caimani in central Brazil.

Growth of Caiman crocodilus yacare in the Brazilian Pantanal

We studied growth of the caiman, Caiman crocodilus yacare, in the Brazilian Pantanal for 27 years between 1987 and 2013.We recaptured 647 of 7769 C. c. yacare initially marked in an area of 50 km2, in two ranches. We were able to determine size at age accurately for 24 male and17 female caimans that had been marked at hatching or less than 1 year old, and recaptured over periods of 5 to 24 years. The other 606 caimans were used to evaluate short-term growth rates. Age-size relationships were estimated using growth models from the Richards family of curves (full model, von Bertalanffy and monomolecular). The form of the relationships differed between analyses based on caimans of known age and analyses based on integration of growth rate on size relationships for caimans whose ages were not known. Individuals showed large variation in short-term growth rates, but data on known-age animals indicated little between-individual variability in long-term growth rates. There was evidence of a small effect of rainfall, but not temperature, on short-term growth of small caimans, but most variation in growth rates was unexplained by variables other than age and sex. Data on known-age individuals indicated that female C. c. yacare generally reach sexual maturity between 10 and 15 years of age. Because of the asymptotic relationship between age and size, deviations of observations from the model for age are larger than for size, and estimates of age at a given size have greater errors than estimates of size at a given age. Integration of growth rate on size relationships may be adequate for estimating size from age in many cases, but accurate estimates of age from size require data on known-age individuals over the size range of the species.

Yacare caiman (Caiman yacare) trim hamburger and sausage subjected to different smoking techniques

BACKGROUND Caiman, as well as having skin that, after tanning, produces leather of high added value, exceptional quality and good market value, also possesses a meat with a remarkably smooth taste and appearance. This study aimed to characterize hamburger and sausages made from Yacare caiman (Caiman yacare) meat trim. RESULTS Hot smoked products contained less moisture than the unsmoked products. Protein and ash were higher, respectively, for hot smoked hamburger and sausage. Lipids had greater presence in hot smoked sausage (9.72%), whereas in the burgers they were higher in the liquid smoked burgers (6.71%). The hot smoked products had lower water activity. Hot smoked products displayed less luminance, but the a* and b* chroma were higher in smoked hamburgers. Taste, texture and general acceptability were significant for the hamburger, whereas for the sausage there was a significant effect for texture, salt and purchase intent. CONCLUSION For all the products, the hot smoking resulted in the lowest acceptability.

Spatial and Temporal Variation in Reproduction of a Generalist Crocodilian, Caiman crocodilus yacare, in a Seasonally Flooded Wetland

We monitored the number of caiman (Caiman crocodilus yacare) nests in two ranches in the Brazilian Pantanal that cover an area of about 50.000 ha for 28 years (1987–2014). The number of nests was related to combinations of rainfall, water level, and number of days with temperature below 20°C, depending on the area. Most of the variation in number of nests could not be predicted by the environmental variables, but could be represented mathematically by a sine wave. We were not able to identify any external driver and suspect that the regular fluctuations may have resulted from an intrinsic population process. Presently, ranches are used as management units under the legislation for ranching Pantanal caimans. However, although some breeding females were recaptured in the area after periods of up to 21 years, most were not recaptured near nests or in general surveys of the area, suggesting that females are not strongly philopatric and that ranches do not represent isolated demographic units.

Several techniques for the preparation of flour from carcasses of the Pantanal alligator (Caiman crocodilus yacare)

Flour prepared via current assay methodologies from the carcasses of the Pantanal alligator (Caiman crocodilus yacare) was analyzed for its chemical composition, minerals, fatty acids, and sensorial profile. Carcasses of the Pantanal alligator, originating from the Coocrijapan scientific zoo, Caceres MT Brazil, were utilized. The carcasses were cooked for 60 minutes in a pressure cooker with water containing 2% salt and 5% chimichurri. The cooked carcasses were then ground and the mass was used for the manufacture of flour via three techniques: non-smoked, hot-smoked, and liquid-smoked. After each technique, the carcasses were dehydrated at 60oC for 3h and were ground. Alligator flour was then produced. The moisture of liquid-smoked flour (10.97%) was higher than that of non-smoked flour (3.78%) and hot-smoked flour (4.43%). The flours provided high protein (57.11% - 58.27%) and ash (23.45 – 26.42%) rates, and were predominantly calcium (6.77% - 7.69%), phosphorus (3.67% - 4.05%), and iron (73.13 – 273.73 ppm/100 mg). Smoked-flour had a better acceptance rate by tasters when compared to non-smoked flour. Results show that flours produced from alligator carcasses had high protein, ash, and mineral rates and a reasonable acceptability by most tasters.

Eimeria spp. (Apicomplexa: Eimeriidae) in Black Caiman Melanosuchus niger (Crocodilia: Alligatoridae) from the Amazon Region, Brazil, with a Description of Two New Coccidian Species

During November 2011, faeces from 23 black caimans (Melanosuchus niger) were collected from the Brazilian Amazon, and coccidians were found in 83% of the individuals examined. Three Eimeria species were found in the black caiman faeces, two of which were recognised as new species and are subsequently described in the present study. Eimeria paraguayensis was found in 17 of 23 animals sampled. Eimeria nigeri n. sp were found in 16/23 animals examined. Oocysts were spherical to sub-spherical, 29.2 × 28.1 (23-32 × 23-30) µm, and 12.1 × 11.0 µm spherical oocyst residuum was present. Sporocyst was ovoid, 15.5 × 9.7 (8-11 × 12-17) µm, and had a Stieda body at a slightly pointed end. The sporocyst residuum consisted of a compact mass of refractile granules. Eimeria portovelhensis n. sp. were found in 16/23 animals examined. Oocysts were spheroidal, 19.5 × 19.1 (16-21) µm, and had 9.0 × 7.8 µm spherical oocyst residuum present. The spindle-shaped sporocysts were 11.0 × 4.0 (8-13 × 2-5) µm and had two apparent Stieda bodies, one at each pole and with one filament curved at each pole. Sporocyst residuum was present, with four or five small refractile granules. The two new species are differenti - ated from the five species of Eimeria recorded within the crocodilian family Alligatoridae.