Rivers and Waters
Except for the rainy season when some of the Arroyos can carry crystal-clear waters, this is not a stage of the walk where the aquatic environment prevails, as it can be expected in a dolomite sierra with pronounced ridges, and at the altitude of the walk. Both the Arroyo de Calaña and Puerto Rico, which, as if for dessert, make up the Arroyo Guadalpín as they unite, are the drainage channels of quite extensive watersheds and as such these streams can maintain water longer in the season, enough to feed some natural pools. But, in general, the suggested itinerary does not let you see these areas.
At the Puerto de los Mochileros you are very close to Cascada de Camoján, a water emergence which lends its name to a whole housing estate. The site of a hermitage in the valley of Arroyo de Calaña was surely chosen because of its seclusion but also the availability of water from a spring which you will not see from the path but which is quite close, about a kilometre and a half walking upstream from the ruins.
A separate mention should be dedicated to the Puerto Rico, whose name reflects the potential resources, represented by two factors of the site: two large flat plains at two different altitudes and a water source in the upper area. The fact that the water source was taken advantage of is confirmed very shortly as you cross the stream at the Puerto Rico Alto where you find an old masonry acequia finished with solid brickwork. The thick vegetation hardly lets you see any cultivated areas but, a little higher up, you can see a few orange trees and other fruit trees while the human infl uence on the area is shown by the ruins of a couple of houses.
Actually Puerto Rico Alto constitutes the border of an enormous ancient water fall which, throughout the millennia kept on creating a bulkhead of a rock cascade based on consecutive layers of travertine loaded with lime. The profile of the semi-circular gorge which overlooks Marbella has numerous crevices and caves which used to be inhabited in prehistoric times, considering the combined factors of a forest environment, shelter offered by the valley and existence of a permanent water source.
Towards the end of the stage there is another area of cascading tufa but much more modest ones. These are two small valleys belonging to the Arroyo del Tajo Negro, which have miraculously escaped the 2012 fire. At the main stream there is a long watering trough adapted for big game species of fauna and, later on, up to the hill with telecommunication antennas on top, there are two more smaller water troughs, with the same purpose, and equipped with a system of floaters that keep the water flowing from a hose which is visible along the path and comes from a nearby water deposit.
At the beginning of Stage 31, at the seaside, you can watch sea birds and coastal birds, together with river species at the stream mouth of the Arroyo Guadalpín. Next, you will be entering the urban sprawl of Marbella, where urban-dwelling birds are predominant. This continues until the tall buildings give way to lower structures surrounded by landscaped areas and an abundance of trees. This encourages the presence of typical forest birds, also because of the proximity of the Nagüeles pine wood. Once you have passed through the pine wood you will encounter stands of trees alternating with areas of scrub and bare rock continuing practically till the end of this stage.
At the beginning you can see gulls, whose abundance and the type of predominant species depend on the time of the year. In winter, the Lesser Black-backed and Black-headed Gulls are most common even though you can also find the Yellow-legged. The last named gull is more common at the end of spring and in the first half of summer. Northern Gannet and Sandwich Tern are also common during migration periods and winter season, so are the Sanderling, Common Sandpiper and other waders, such as Turnstone. Mallard, Great Cormorant, Grey Heron, Little Egret and Cattle Egret can also be seen along the first section of Stage 31, as well as the progressively more common Monk Parakeet.
As you enter the built-up area, Common Kestrel, Eurasian Collared Dove, Pallid and Common Swift, Barn Swallow, House Martin, Common Blackbird, Black Redstart, Common Chiffchaff, Spotless and Common Starling, House Sparrow and Serin are the most common. When passing through the area of low houses and extensive landscaped zones, you will notice that both the Blackcap and the Sardinian Warbler turn up, also Great Tit, Coal Tit, Common Chaffinch, and other typical woodland birds. In the “proper” pine wood, where the savin juniper, wild olive and mastic form part of the undergrowth, you will be able see the Common Wood Pigeon, European Turtle Dove, Short-toed Tree Creeper, Goldfinch, Greenfinch, Serin, Eurasian Siskin and Crossbill, besides the already named birds.
The Nagüeles pine wood is an excellent place to see the Crested Tit, an easy to identify bird because of the tuft of feathers on its head. The bird has a black collar encircling its whole neck and if you are close enough you will notice the striking red eye colour. This species is much easier to hear than to see, however with a bit of patience you will end up spotting the bird, always accompanied by other individuals of the same species.
Past the pine wood the many ups and downs lead through a sequence of cols. Dense tree copses alternate with dolomite limestone zones where herbs and esparto grass rule. The European Robin and Bonelli´s Warbler nest around the streams where Song Thrushes and Redwings congregate in winter. Open areas are the domain of the Common Stonechat, Sardinian Warbler and Crested Lark, and this is a good moment to start paying attention to the sky for a very likely sighting of a raptor. Besides Common Kestrel, you can see Short-toed Eagle, Common Buzzard, Bonelli´s Eagle, Booted Eagle and Golden eagle, as well as Goshawk and Sparrowhawk. Other well represented species in the area are the Red-necked Nightjar, Little Owl, Bee-eater, Pallid and Common Swifts, which can form great flocks at the foothills of the sierra in search of food, plus the Red-rumped Swallow.
At certain points of Stage 31, such as around the open-air pyrite mines, you can find sites which harbour the Eagle Owl as well as wintering and breeding populations of Crag Martin.
Before the village of Ojén comes into view, at the outskirt villas, you will be walking through a mature pine wood where the already named forest species turn up again, together with the Tawny Owl and Scops Owl. Along the last section of Stage 31 in the shady areas with trees, such as the surroundings of the Arroyo del Tajo Negro, the scarce Iberian Chiffchaff nests, plus you will be able to spot the Long-tailed Tit. Same environment holds European Robins year round, and one or two Hawfinches might make an appearance.