The last Friday we had the opportunity to go personally to the forest with the FSF (Friends of Shimoni Forest), and enjoy of this endangered ecosystem with the persons that are fighting harder to preserve it. Hassan, one of the three trained guides of the FSF, walked us through the forest, leading us to some of the most remote parts, most of them new to us. This is the same walk tourists take when they come to visit the forest.
The "tree of oblivion", a parasitic vines who once strangled a baobab
For all those who don’t know it yet, the FSF is a CBO (Community Based Organization) based in Shimoni. It was founded as an initiative of the community, with the help of GVI. Their objective is guaranteeing the conservation of this endangered forest, trying to develop sustainable uses of this forest which is so necessary for their livelihoods. One of their most successful projects was the creation of a forest tour, and the money they get from tourism is put back onto the community, in the form of different projects of grants to students.
Hassan the forest guide, during one of his detailed explanations
And what was the result of our guided tour through the forest? A lot of Angolan black and white colobus, sykes monkeys, hornbills, tons of insects… but it was not only about what we saw. Hassan gently provided us with tons of background information and different stories about the forest, the plants and their medicinal uses and about the local culture. We visited one of the “kayas”, a sacred place of the forest where spirits inhabit and which serves for oration and prayer. After enjoying of such a trip, it’s not strange that tourists always turn out of the forest enthusiastic about all they have seen.
Below are a few of the recent sightings our forest team have seen around the area during various surveys.
Whip Spider (Phrynicodamon scullyi). Use its elongated front legs not for walking but as feelers. These arachnids usually move sideways using their sensory legs to feel for prey that is then caught with the large raptorial pedipalps.
Flap-Necked Chameleon (Chameleo dilepis). With its huge distribution, relative abundance and willingness to utilize urban areas this chameleon is under no conservational threat.
Malachite Kingfisher. Spotted resting on a low branch during a night walk through the forest.
Yellow-Headed Dwarf Gecko (Lygodactylus luteopicturatus). Endemic to South-Eastern Kenya and Eastern Tanzania this brightly colored gecko is able to rapidly undergo a color change turning completely black when angered or threatened.
The speckled lipped skink (Mabuya maculilabris) is common in East-Africa near natural water sources. They are beautiful and quite subtly colored animals. This afternoon we were lucky enough to witness some of their mating behavior.
Male (left) grabbing some of the female’s skin possibly inducing mating.
The four –toed elephant shrew (Petrodromus tetradactylus) is a brown, rat-sized elephant shrew with a large head and ears its legs are light coloured and very slender with only four toes. This particular shrew is found distributed throughout SE and central Africa found primarily in dense evergreen undergrowth in caesalpinoid forests, woodlands and thickets. It feeds mainly on ants and termites but is also known to eat crickets, grasshoppers and other litter invertebrates therefore relying on a rich leaf litter composition for food and nesting. Like many small forest mammals it is most active in early morning and evening. Last week GVI volunteers found a dead four-toed shrew in the coastal forests surrounding Shimoni and have been working to preserve the skin as record.
Skin of four-toed elephant shrew
Last week in Shimoni West forest we came across the shed skin of a four meter African rock python, one of the largest snakes in the world. Individuals have been known to reach five and a half metres in length with a girth of almost a meter. They don’t have the ability to inject venom but can deliver vicious bites and are powerful constrictors. Close to where we found it there was a huge hole in the ground, likely to be it’s home. Everyone would love to see one and we’re making sure to organize a stakeout up there shortly.
Shed skin of Southern African Rock Python
Their current status in Africa is not threatened however like most snakes they are intolerable of human development therefore as development increases the snake population will inevitably decline. Due to their size these snakes are often hunted and killed for their skins and meat.
Yesterday we went on a walk to a village west of Shimoni named Kibuyuni. We were looking to see what wildlife we might encounter in the forest surrounding the village. However, we never really managed to get to the village. There were just too many birds to spot everywhere.
Especially noteworthy were the raptors (birds of prey). Africa at large and Shimoni in particular is the winter home to many migrating birds, among them raptors. One of the most common winters we see every day is the black kite Milvus migrans. Black kites are medium size raptors that favour open fields as hunting grounds. They are frequently seen above recently ploughed hunting small animals that were scared out of their hideouts.
A black kite in flight
Another impressive winterer we have seen in our skies in the past week is the steppe eagle Aquila nipalensis. This is a rather large brown eagle and has very impressive sight.
But maybe the most interesting factoid is about a local hawk species: the harrier hawk Polyboroides typus. On our way to Kibuyuni we were lucky enough to get a very good view of a harrier hawk flying low above our heads and perching on top of a coconut tree. What was most surprising was that the bare patch of skin on the hawk’s face was bright red and not yellow as is instructed in the field guide and as we saw in our previous sightings.
Further investigation and reading on the species taught us that harrier hawks’ facial skin turns red when they are excited!
Maybe the hawk was just as excited as we were upon seeing her!
Among the additions to GVI’s surveys are our Indicator plot studies. Indicator plots enable an intensive study to be made of a 50m x 50m sample of the forest habitat. Several surveys will be carried out within the plot to gauge levels of disturbance, biodiversity, and vegetation makeup. So far, two such surveys have been carried out: firstly, two butterfly traps were installed, and secondly, an active search was done, in which surveyors were encouraged to be as proactive as possible in finding species (in contrast to a passive search where animals are looked for without disturbing anything).
The net traps, suspended from the branches of trees and baited with fermented bananas, had attracted one butterfly in each, both large and very attractive. Before taking them out it was important to check that nothing likely to bite or sting had also entered the trap. It is daunting at first to grab hold of a butterfly but these animals are large and robust and once you have your hand around them it is relatively easy to manoeuvre them so that you are lightly grasping the thorax with the other hand, enabling a photograph to be taken of both upper and under sides to aid identification. Consulting the butterfly guide later, one species appeared to be a striking female mocker (Papilio dardanus polytrophus), and an equally striking Charaxes brutus.
Looking around at the start of the 15 minute active search, it appeared that the plot was devoid of life, but once the leaf litter was disturbed, stones and logs rolled over and stems and leaves examined, animals became evident – between three of us we found a sharp-nosed ridged frog, a tiny toad and even one foot-long snake.
GVI has started conducting 2 new surveys in Shimoni Forest, and the first was called “Tree Survey”. Which is all well and good, but how exactly does somebody go about surveying trees – and why?
Big trees are unquestionably among the most important aspects of any forest, providing both food and habitat, either directly or indirectly, to a vast number of animal species. Yet they’re often also the most vulnerable aspect as well – they’re much sought-after for charcoal and timber, and obviously they take many years to regenerate once taken down. Additionally, some tree species are more desirable than others for making building materials or fuel, and that means those species are disappearing faster than others, altering the ecological balance of the forest.
- Forest team conducting survey-
And one more note – when Julie Anderson studied Black and White Colobus in the area, she identified 14 species of tree that provide for 75% of Colobus feeding activity. By identifying which species are present along our forest transects (and in what abundance), and by tracking this data over time, we can get a much better idea of the composition of our forest, the patterns of human disturbance that threaten it, and how this could impact our Colobus population. To that end, we’re also measuring the trees themselves, in terms of trunk diameter and the height and volume of the canopy, both to see whether these factors correlate with Colobus presence, and as a method for analyzing the carbon sequestration potential of East African coastal forests – something that has never been looked at before.
Every time a group of volunteers heads into the forest, there is one form that always goes with them: Casual Observations. It’s our most basic survey, run every day from the moment we leave the house until the moment we step back in the door at the end of the day – every animal we see, we write down, along with the time and location of the sighting.
Over 4 years, this has given us a huge amount of data (more than 5000 documented sightings!) But as yet, not much has actually been done with it all, which makes it both a challenging and actually pretty exciting task (at least, as exciting as messing around with Excel spreadsheets can be) to go through it all and find out what this mountain of data actually says about our forest. This analysis is still in the early stages, but I’ll keep you posted as we continue digging through it. But for now, here’s a nice early result:
Angolan Black & White Colobus sightings by transect
This chart shows how frequently we’ve seen Colobus monkeys on each of our transects in Shimoni East forest. We have 6 transects, or straight-line paths, in Shimoni East, and all of our surveys are run on these. The “Individuals/Effort/# of sections” bit just means the number of monkeys we’ve recorded, divided by the number of times we’ve been on that transect, divided by the size of the transect – by doing this, we account for the fact that some transects are visited more often than others, and all of our transects are of slightly different sizes.
So what does it mean? Well, more detailed analysis is needed before we can say anything conclusive, but potentially something quite important: Transect 1 (where the big spike is) is located very close to the coastline – so the implication of our Casual Observation data seems to be that there is a significantly higher density of Colobus in forest near the coast than further inland. This would be a very interesting finding on its own, but when you also consider that the coastline forest is currently suffering most from degradation and land development, it makes it all the more important, highlighting how critical the situation in Shimoni forest currently is.
A group of forest staff and volunteers recently set out to do a primate community survey on transect one. This involves walking along the set forest transect and looking for troops of Colobus and Sykes monkeys. Transect one has been subject to substantial disturbance and felling in the past due to its prime location on the coast, easily accessible by dirt track – a few sections of this transect that run through a large clearing that we call Mordor- due to its resemblance to the Lord of the Rings setting! This clearing has been present for over 18 months, although over recent months has been steadily increasing in size. This week the group found that a large area past Mordor, further along our transect had also been cleared within the last few weeks.
Charcoal burning in Shimoni Forest
The good news is that the group were still able to spot a troop of Colobus during the survey, but an unsettling fact is that some of the monkeys were on the ground which is considered unusual behaviour for a species that favours the upper canopy. The behavioural and disturbance data we get from our transects is a great way of establishing how the loss of habitat is affecting this already rare primate.
Trees are felled for timber and to clear land, reducing habitat for the rare Colobus
Disturbance in the form of pit saws, charcoal pits, and clearings is becoming more and more common place on all our transects, and we are collating all evidence from 2007 to present to find out exactly how this is affecting all our target species.