At present, this section is limited to the semi-arid interior of Ceará. Accounts of other habitats, like humid mountain forest, will be added later.
The interior of Ceará
Climate and rainfall
Vegetation
Mãe-da-lua private reserve
Vegetation
Mammalian fauna
Water situation
Fazenda Canaã
Vegetation
Water situation
The climate in the semiarid interior of Ceará is hot and tropical, with little seasonal variation in temperature. Average rainfall in the main study areas, Pentecoste and Itapajé (which are adjacent to each other), is around 850-950 mm/year (Atlas do Ceará 1997), but the amount of precipitation varies a lot between years, and drought periods of 1-3 years are common. The rainy season starts around January (sometimes already in December, but sometimes as late as February or March) and lasts a few months, normally ending in May or June.
During the remainder of the year, there is nearly no rainfall. Most trees loose there leaves, and many rivers, lakes and water reservoirs dry out. A number of bird species leave the area during the dry season.
In Pentecoste, Itapajé and neighboring municipalities, the original caatinga dry forest has disappeared. I have not yet seen any area of undisturbed caatinga vegetation in this region (or elsewhere in Ceará). Today, the dominant types of vegetation are:
- Caatinga regrowth. I would estimate that caatinga regrowth covers presently at least half of the local countryside. This vegetation continues to be severely degraded by slash-and-burn agriculture, by logging for charcoal and firewood, etc. Foraging of domestic animals like goats, cattle and pigs effectively stops the recovery of most tree species.
-
Plantations, especially of Anacardium occidentale ("Cajueiro"), the tree
which produces cashew nuts; and cultures of manioc, maize and
beans.
- Open areas for grazing cattle and sheep.
This RPPN (private nature reserve) is located in the municipality of Itapajé in the state of Ceará, about half way between the capital Fortaleza, and Sobral. It includes the east and north sides of a mountain range called "Serra dos Vertentes" (about 400 ha), and lowland south of the mountains (about 360 ha). See photo. The maximum elevation of the mountain range is 650-700 m.
Large parts of the property were covered by cotton plantations until about 1970. The cotton areas included the lowland and easily accessible hillsides, but did not extend into areas of more difficult access, like steep hillsides and mountain tops. On one of the mountains existed a banana plantation, which was abandoned in the late sixties or early seventies.
From the 70ties onwards, the farm was used mainly for grazing cattle in native pasture (i.e. in secondary growth caatinga), and for slash-and-burn subsistence agriculture. In addition, large quantities of fire wood were extracted. The areas of difficult access, and some of the former cotton areas, were left largely undisturbed.
The non-profit group "Associação Mãe-da-Lua" bought the land in November 2006, and has transformed it into a nature reserve. The vegetation is now protected, and hunting of any kind is strictly forbidden.
The flora of the reserve is varied. In general, the areas of difficult access are best preserved. In part of the mountains, the forest is growing undisturbed since 30-40 years. There are even areas where the forest has never been cut, but these did suffer from wildfires.
A survey of the vegetation of the reserve, by a botanist or a similarly qualified person, is not available at this time. The following information is preliminary, and summarizes my own observations and estimates.
1. Mountain range
- Mature secondary dry forest, age 35 years or older. High biodiversity. In total 50-100 ha. See here.
- Mature secondary sub-humid forest, age 35 years or older, commonly called "mata fresca". Exclusively at the mountain tops, at an elevation of 600 m or more. This forest has tall and big trees, and is characterized by "samambaia", growing from the tree branches. See photo. 5-10 ha.
- Secondary dry forest, age 15-35 years, especially in the valleys and the lower hillsides. The most common tree species here is Sabiá (Mimosa caesalpiniifolia Benth). About 200-250 ha.
- Areas destroyed by farming and wildfires during the last 10 years. Poor vegetation. About 100 ha.
- Secondary arboreal Caatinga, age 20 years or more. About 100 ha.
- Secondary growth, age 5-20 years (including "capoeiras"). About 120 ha.
- Areas devastated during the last 5 years, by slash-and-burn agriculture, wildfires and wood extraction. Poor vegetation. About 140 ha.
Among the mammals which prey on birds, foxes are the most numerous. I see a fox or two nearly every time I go for a walk through the reserve. The species is possibly Cerdocyon thous. Another carnivore is the racoon Procyon cancrivorus, whose characteristic footprints can frequently be seen.
At least two species of wild cats live here. One is Felis yagouaroundi, the "Gato mourisco". At the end of 2007 and beginning of 2008, I have repeatedly seen an adult cat (presumably a female) followed by 3 youngs. The other species has the size of a domestic cat and the colors of a jaguar (yellow with black spots); this is Felis tigrina, a cat species threatened by extinction according to IBAMA 2003. The locals call it "Gato maracajá" or sometimes "Gato pintado".
The Hog-nosed Skunk Conepatus semistriatus was seen on one occasion.
Two primate species are rather common in the reserve, namely the marmoset Callithrix jacchus and the Brown Capuchin monkey Cebus apella.
In spite of intense hunting (protein supply for the local population, as some politicians call it), at least one deer has survived, see photo. I believe the species is Mazama americana, the Red Brocket.
Among the Edentata, we have the anteater Tamandua tetradactyla, which reportedly does not only eat ants and termites, but also bird eggs (Von Ihering 2002); and at least two Armadillo species, with the brazilian names "Tatú" and "Peba".
There are also various bat species, among them vampire bats. The latter attack not only large animals like horses (they repeatedly sucked blood from my horse) and cattle, but apparently also large birds like domestic chicken. Presumably, they could be a danger for our guan population (Sick 1997, p. 275).
The most visible rodent species is the preá. It looks like a brown version of the domestic guinea pig Cavia cobaya, and has about the same size. For this reason, I initially assumed that the species is Cavia aperea, but this could be wrong. According to several publications about mammals of the Caatinga, preá is Galea spixii. See e.g. Streilein 1982, Oliveira et al. 2003; but see also Rocha 1948.
Another rodent is the punaré Thrichomys apereoides. It was once very common in the reserve, but hunting has reduced the population greatly. The mocó Kerodon rupestris appears to have been present in the past, but since we bought the reserve in 2006, I have not yet seen a single individual.
The meat of these three rodent species, preá, punaré and mocó, is often sold at the market in Itapajé.
For identifications of the mammalian species, I consulted Eisenberg and Redford 1999, Von Ihering 2002, and others, as cited in the text.
There are 2 waterholes in the hills, and 2 more in the lowland. All 4 water holes have sufficient water the whole year, and are much visited by birds and mammals, though the water is a little salty.
In addition, there are 2 small reservoirs. One of them has water during the whole year. However, every day, many goats enter the reserve through holes in our half-rotten fence, and visit this water reservoir. No surprise, then, that the vegetation around the reservoir is in sad shape. The other reservoir is fenced off against the goats; it supports a lot of wild-life during the rainy season, but normally dries up in the second half of the dry period (between October and December).
Furthermore, during the rainy season, several small streams run through the reserve. In neighboring farms, there are other permanent water holes and reservoirs.
This farm is located in the municipality of Pentecoste in the state of Ceará, about 60 km west of the capital Fortaleza. The following description applies only until June 2006, at which time I sold the property.
Most of Fazenda Canaã is covered by secondary growth caatinga in various stages of recovery, depending on the extent of previous degradation, the length of the recovery period, natural soil quality etc.
-
In large areas, the arboreal flora consists nearly
exclusively of small "pioneer" trees, like Croton sp. ("marmeleiro")
and Combretum leprosum ("mofumbo").
In some instances, crops were cultivated in these areas
only a few years ago; in other cases, the last slashing-and-burning happened
over 20 years ago, but the damage to the soil was such
that only the most hardy trees have since grown there.
-
Elsewhere, the recovery of the native flora is more advanced,
as can be told by a larger number of tree species and higher growth.
-
There are even parts (in total maybe 10% of the fazenda) where
the native vegetation has regrown largely undisturbed
for a long time, for 30-40 years or longer. Here,
many trees are 8-10 m high, and there is a rich biodiversity.
This applies also to the gallery forest of a river,
Rio Melancias,
which traverses the fazenda (see below).
- Occasionally, smaller stretches of semi-open bushland can be seen.
- About 40 hectares are open grassland for grazing of sheep and cattle, and a few hectares are plantations of caju trees.
Availability of water is an issue of particular importance in a semi-arid environment. The water situation of Fazenda Canaã is the following:
- There are 4 reservoirs (dams), each covering a surface of 1-3 hectares when full. These reservoirs normally have some water during the entire year, but they can dry up if there is little rain for 2 consecutive years.
- A river, Rio Melancias, crosses the fazenda. The river has running water during a short period of the year only, maybe 1-3 months. After the rains, the river stops flowing, but standing water can be found in numerous water pools in the river bed, for another 3-4 months. This river has a relatively well preserved gallery vegetation, and attracts a lot of bird life; unfortunately, it also attracts illegal hunting.
- Furthermore, there is a shallow lake, the "Lagoa Velha" , which extends over several hectares. In most years, during the dry season, the lake dries up; in the following rainy season, the lake area then first becomes a marsh, and, depending on the amount of rain, subsequently either turns into a true lake (up to 1.5 m deep), or remains swamp until it dries up again several months later.
- There is a big water reservoir in a neighboring property, about 2 km away (Fazenda Mastruz-com-Leite). There, water is permanent and abundant.