segunda-feira, 28 de novembro de 2011

Goodbye Azores part 2: spiders, what else?

After the first seven months in the Azores my job was little more than fieldwork logistical tasks. After the sorting of samples belonging to the BALA II project commenced, I was finally getting in touch with the native fauna on the microscope, and soon realized that the diversity was so small that nearly all Azorean endemics and native spider species could be easily recognized and distinguished from each other.
In the field, it is similarly easy to distinguish the few Azorean endemics. At canopy level (bear in mind that I only refer to samples made in native laurel forest) you find Savigniorrhipis acoreensis (Linyphiidae), Rugathodes acoreensis (Theridiidae), Sancus acoreensis (Tetragnathidae), Gibbaranea occidentalis (Araneidae), Lasaeola oceanica (Theriidae) and Acorigone acoreensis (Linyphiidae), all of them, even the tiny ones, being sufficiently different to be distinguished in the field. Just above ground level in exposed areas, you can find the nursery webs of Pisaura acoreensis, the largest endemic spider of the archipelago, especially between July and September. At ground level, several cryptic endemic species are not so easily found, like the erigonines Porrhomma borgesi, Walckenaeria grandis or Minicia floresensis, the later of which can also be found at canopy level sometimes. The small jumping spider Neon acoreensis was caught only twice bye me by direct hand sampling near the ground level.
At soil level in shady places you can also find the delicate sheet-webs of the linyphiine spider Leptyphantes acoreensis. All the mentioned spiders were supposed to be spread throughout the entire archipelago, and that sticks at the truth for all but one.
Other endemics are single-island endemics, and of these there aren’t much. Aditionally, I investigated some of them in collaboration with other specialists and at least one of them seems to be a synonymy with a species present in the Mediterranean. Other of these single-island endemics are subject to a somewhat suspicious view, being described in the basis of very small morphological differences by an author widely known for being a careless “splitter” and others remain unquestioned like Meioneta depigmentata (Linyphiidae) from Flores, Acorigone acoreensis (Linyphiidae) from São Jorge or Turinyphia cavernicola from Terceira (Linyphiidae).
Now, the new stuff:
Since these are all unpublished species, I will not write relevant information regarding their habitat and location. Please understand this.

A new species, sister of Savigniorrhipis acoreensis, was found present in one island only. Incorrectly identified material was present from previous works. This new species, more than morphologically, is ecologically separated from S. acoreensis, because it is present at ground level, while the latter is present at canopy level. This finding   provides a new look on the genus Savigniorrhipis, and hopefully it will either be validated or synonymised, but with a better analysis that that provided in its original description. Here it is the new species, it has a name, but I can’t reveal it by now as this would unmask the location of this tiny erigonine spider (on the bottom, the previously known endemic species S. acoreensis, both are females):

Also in the family Linyphiidae, one endemic species is now separated into 3 different species, one in each group of islands. The scientific work regarding these 3 species will take some time to be prepared and by now I can’t even confirm their genus with certainty.

These last fellas will be one of the major concerns regarding manuscripts in the next months for me. For these spiders I need the help on a more experienced arachnologist. When that publication sees the light of day, I will post here some further info on these little guys.

quinta-feira, 17 de novembro de 2011

GOODBYE AZORES: PART 1, the wilderness

Not long now until my return to the mainland. My stay in the Azores will end in 2 weeks and although I know that I must be back in April and May and later again for my Masters’ viva, the bulk of my Azorean experience is done. I arrived in June 1st 2010, which accounts for 1 and half year in Terceira. I sense that it was a very positive episode in my life. I will write some thoughts, while I psychologically prepare myself to get back to base…

I feel that I had a great privilege, in the sense that my work allowed me to know much more than what the regular tourist does, like the last remnants of native laurel forest in the Azores, and many of the biological entities of this particular habitat. While the word “forest” is sometimes inappropriate to describe the shrub-like appearance of native forests, especially those in high altitudes, the singularity of this landscape is remarkable. It changes the concept of what we imagine when we think of the word “forest”. Plant diversity is not great, given the size and isolation of this archipelago (as well as most other groups of organisms), but several species give the native forest an especially different view of all the other forests present in the Portuguese territory. Twisted logs of Juniperus brevifolia, topped by a bonsai-like canopy give the Azorean forest quite the looks, in all the islands where it can be found. Usually, the ground is covered with Sphagnum mosses, and it’s very comfy to sit down in a natural pillow, considering you don’t care about wetting your butt! Other dominant arboreal endemic species or subspecies are Ilex perado azorica, Laurus azorica, Vaccinium cylindraceum, Frangula azorica, Erica azorica. I will always remember the day when to do beatings in Terra Brava Reserve in Terceira I, Sandra and François Rigal had to climb Ilex trees like we were kids, otherwise we wouldn’t reach the canopy and the task at hand would be left incomplete. It’s not easy to find places where climbing the Azorean native forest is a challenge, especially when you are many kilos heavier than what you were the last time you attempted this.

If you go to Pico look in the margins of the longitudinal road that crosses the island: you may find patches of another endemic plant that is seldom found in the other islands, Euphorbia stygiana. It should be the largest euphorb in Portugal. The dead twigs and logs of this plant are the preferred house of several species of endemic insects that either are xylophagous and eat the dead wood themselves (weevil Calacalles droeuti) or mycophagous beetles of the genus Tarphius that feed on the fungi growing in the dead wood.

Unfortunately, native forest patches are relics, occupying about 0,5% of the total Azorean area. These remnants exist mostly due to the hard accessibility and high altitudes, which rendered these sites free of the reach of cattle industry. In nearly all the lowlands the landscape is very dull, with green squares of herbs separated by walls or patches of Cryptomeria japonica, an exotic tree brought to the islands to produce wood. Speaking of which, the wood is not good, but in the past decades, the regional forestry services planted this tree carelessly throughout the islands, and in very rainy seasons it is common to see some of these trees down, especially in steep places. Also, very little plant life grows in Cryptomeria forest other than Cryptomeria itself, due to the great shadow that these large trees provide.

Besides this exotic tree, the native forest is now dealing with several other invasions, being the worst cases those of Hedychium gardnerianum and Pittosporum undulatum. Both of these plants came to the Azores due to its ornamental factor, and escaped from urban areas. The former came from Asia and the latter from Australia. Larges areas are now affected by these aggressive invaders and although some eradication efforts are being made, one is very pessimistic about the future of the Azorean native forest.

To finish this, I point out 3 “Natural Places You Must See in the Azores”:

  • Morro Assombrado in Terceira: one of the most spectacular patches of native forest. The rugged geomorphology of these volcanic ridges is amazing! You must take care here, you can get lost easily, take someone experient in these places with you and be careful not to fall down one of the many holes.
  • Caldeira of Serra de Santa Bárbara: this is the largest natural reserve in the Azores, and the Caldeira, its center. To be down there in the middle of this pristine site may not be easy in the future due to the upcoming restrictions and management by the Natural Park of Terceira. Hiking down there is also not easy! Watch out for holes.
  • Morro Alto in Flores: this is the Sphagnum paradise! Once you reach the top you soon realize that the ground is made of bryophites, even if you are just following the road, because sometimes huge Sphagnum “pillows” made of several colors hang just above the road, dripping large amounts of water. If you add the lagoons and waterfalls on Fajã Grande, you can spend one week wandering about this nice little island, and you have plenty of nature to see. Being able to take a photo in a workplace like this is a privilege (yes, I just finished working).