April 2017 Monthly Report

April 2017 Monthly Report April brought about a distinct change of season, with the weather starting to produce colder days and the Aloes revealing their red bloom en mass. This month’s report shares the increase in number of fisherman to the area in the usual compliance management section, an article on biological control that may have led to human health issues in our area, environmental education activities in the form of radio talk shows and posters centred around plant appreciation day, and a short video that highlights some of the activities we get involved in. The Conservancy also saw some turtle and bird rescues which we report on, after which we then round off with our featured monthly species profile. A drone image captured the ocean, land and sky coming together on Fransmanshoek Peninsula Aloes are blooming! In April the Bitter Aloe, Aloe ferox, has adorned the Fransmanshoek Conservancy with its fine, fiery bloom. The Rangers spotted the first flowering Aloe at Springerbaai and soon the rest followed in a westward blooming sequence. The flowers came at a time when little else was flowering, gracing us with a satisfactory display of nectar drinking birds. Its flowers also attract various insects, which in turn attract a larger variety of birds. 2 April 2017 Aloe ferox usually only starts blooming from May to August and in colder areas it may even be delayed until September, so keep a look out for the late bloomers. Aloe is derived from the Latin languages and refers to the dried juice of the leaves. Ferox refers to spiny appearance on the leaves and means ‘fierce’ or ‘war-like’. The start of the Aloe’s bloom. Compliance Management The Rangers were kept very busy this month during their marine compliance patrols along the Conservancy coastline. During the month of April, a total of 236 recreational fishing, spearfishing and bait collecting permits were checked by Kei and Anton. Of the 236 permits checked, 45 persons (19%) did not have a valid permit in their possession and were issued a friendly warning. A strange and rather unpleasant deposit of large amounts of Redbait, Pyura stolonifera, washed ashore on our beaches, particularly along the Kanon beach in Visbaai. The large quantities of dislodged and beached Redbait caused a bit of a stir and had people questioning the reason behind this smelly phenomenon. Typically, during storms out at sea, the weather can cause the waves close to the coast to increase in size and intensity. The waves break with increased force and the Redbait are positioned right in the frontline and stand no chance as they get knocked off the rocks they are attached to and wash ashore. 3 April 2017 It is important to keep in mind that even though these animals are washed out, a person may still only take out 2 kilograms of any size per day. Redbait is a popular bait choice for anglers, but it is also a source of food for the various animals found on the beach and to some people of the southeast coast. A graveyard of redbait lining the beaches’ highwater mark. Biological Control: out of control Sometimes the history of our decision-making and the consequences thereof do not stop us from repeating the same patterns of mistakes. Historically in South Africa and particular over the last 100 years, conservationists, naturalists and agriculturalists introduced alien plants and animals for a whole host of reasons that may improve the livelihood of mankind. Regardless of their intention, we are today taught in Natural Resource Management and commonly know that these decisions were often short-sighted and have had perceived negative environmental consequences that we are still having to deal with today. A well- known example is the introduction of a whole suite of Australian plant species for purposes of dune stabilisation. The consequences of invasive alien introductions include habitat and species loss or biodiversity loss, increased fire regimes, system changes and whole habitat transformations. All these environmental issues are of concern to us as they affect the world around us which sustains us. However, these affects are akin to the ‘Boiling frog’ parable whereby our lives are negatively affected unseen or on too large a time scale for us to realise. More recently, to deal with these consequences, a host of methods have been employed by scientists and managers in managing the situation. One such popular method is biological control, or biocontrol. This is when a biological organism, usually an alien organism itself originating from the same area as the alien invader, is employed to try to slow the spread of the invasion through various means, such as parasitizing the seed producing parts of the invader plant or weakening the plants growth through disease. Often these alien bio-control organisms go through extensive trials to determine if they will be a hazard or a help the situation. The problem is that these trials usually only predict the impact for 10 to 20 year periods, and don’t necessarily forecast centuries into the future. What if these introductions of alien organisms to control out-of-control organisms are a short-sighted response that carry their own unforeseen consequences? What if these consequences have a direct or indirect effect on human health? 4 April 2017 Over the past three years, and particularly recently, we have begun to witness a series of reports and experienced first-hand an outbreak of skin irritations or “bites” on nearly all persons that work or live near dense stands of Rooikrans trees, Acacia cyclops, from around February to April each year. These incidents have been occurring in the Fransmanshoek Conservancy on the Southern Cape coast near Mossel Bay, and I cannot talk for the other areas with similar Rooikrans infestations. The bites tend to occur all over the body and cause uncomfortable itching. In some cases, the bites have led to hospitalisation following serious allergic reactions. There is an association and somewhat of an assumption that it is being formulated by local inhabitants that the same insect responsible for causing the immeasurable amount of galls (a vegetative-type looking growth) on the Rooikrans flowers is responsible for these bites on humans, due to a population explosion of some kind. Irrespective of the cause, human health is being adversely effected here. I believe there is some correlation and will share my findings. There have been several bio-controls released for the control of Rooikrans, from a host of seed-feeding weevils to seed-reducing gall-forming midges, all of them being highly successful at reducing the seed production of the alien invasive tree. Here in the Fransmanshoek Conservancy, we can at first glance see that the Rooikrans flower parts have been transformed into vegetative type galls. This is the only visual evidence of biocontrol that is seen easily without a microscope. A more thorough inspection with magnification may reveal all the different biocontrol insects, which are usually too small to distinguish with the naked eye. Assuming we take this visual evidence of the countless flower galls as an initial investigation, this gall is the work of the small fluted galler midge, Dasineura dielsi Rübsaame. This midge parasitizes the Rooikrans flower over the peak flowering period in summer-autumn as part of its reproductive cycle. It implants its larvae in the Rooikrans flower. The larvae then form woody fluted galls on the ovaries of the Rooikrans flowers, thereby preventing any further development of the flower and ultimately the seed. The galls eventually fall to the ground and the adult midges hatch and emerge to repeat the cycle when the Rooikrans produces flowers. These midges have been very successfully employed to slow the seed production of Rooikrans with high gall densities of several thousand often present on a single tree, effectively reducing the seed production up to 95%. Dasineura dielsi female ovipositing on Rooikrans flower. 5 April 2017 The wooded fluted galls of Dasineura dielsi. Nothing in a search of the literature indicates that these midges are parasitic on humans, in any of their 4-life stages, contrary to our speculation. They are only parasitiods on vegetation. What is very interesting is that they have been known to hatch and emerge to the adult stage over the period February to April, which is coincidentally the same period we have experienced these “bites” and itching. There may however be another possible explanation. Indigenous predatory insects have taken a liking to parasitizing and feeding on the midge populations. Perhaps the indigenous predatory insects have, because of the high numbers of galler midges, also experienced a population explosion and perhaps it is these guys that are responsible for the skin irritations we are experiencing. There are numerous known wasps that parasitize the galler midges’ larvae that are mentioned in scientific literature. These are mesopolobus sp, torymus sp, family Platygastridae and synopeas sp. These wasps are small and will implant their larvae into the galls formed by the galler midge. The wasp larvae will parasitize the galler midge larvae and the emergence of the adult wasps coincides with the emergence of the adult galler midges. It is very likely that these minute wasps are stinging local human inhabitants and injecting wasp toxin into the human’s body in very small quantities. This causes irritations privy to what we have been experiencing. Thus, we are suggesting that what we are experiencing are stings, and not bites. This is supported by the fact that some people are having allergic reactions, which could be reactions to the toxin injected when stung by these wasps. Further investigation is still required to determine if this is really the case.

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