Owl Box Project
Owls are both fascinating and beautiful animals. Their presence in your garden offers hours of intriguing viewing, Furthermore, they provide an efficient means of pest control. The two most common species in Gauteng are the Barn Owl and the Spotted-eagle Owl. Whilst these owls are strikingly different in appearance, both species exhibit many similar adaptations. These adaptations range from their specially designed wings, which allow them to fly silently whilst listening for prey during flight. Light sensitive eyes enable them to detect prey in low light conditions and it is these complex design features that are the basis for the success of the owl as a species. However, these specialisation means that owls are relatively susceptible to environmental changes and this is where the project comes in. Whilst there is no doubt that there is an Owl population within Gauteng it remains unclear as to how long this will be the case. The key to extracting maximum enjoyment from your owl box is simply INTEREST. Be interested and observant, otherwise, those golden moments and unforgettable interactions will be missed. The first flights from the box, the youngsters catching insects on the lawn. These moments occur all the time…
Owls breed from late autumn through summer. However breeding habits are very variable, relying primarily on prey availability and suitable breeding sites, likewise, the number of eggs produced varies dramatically. Barn Owls (Tyto alba) are able to alter their breeding habits in response to prey numbers, the greater the abundance of prey the greater the number of chicks produced, allowing owls to better combat prey population sizes. This is exceedingly useful in controlling populations prone to growth explosions i.e., rodent and insect species. During the period in which the owls breed activity is centred around the box. Food exchanges and vocalisation is common and is a key indication of breeding activity, this is the most exciting period. The owlets leave the box approximately 4-5 weeks after hatching, however, they are poor fliers and very curious which enables one to observe them closely. Youngsters are inclined to perch close to the ground and exhibit all the playfulness of young kittens and watching them play on the lawn is a truly unforgettable experience. During the remainder of the year, the box will see less activity, although once owls have bred in the box the will continue to utilise it year after year. The owls will remain in the vicinity in order to protect their territory of which the box is an important component.
EcoSolutions is responsible for the installation and the running of the Urban Owl Box Project. The owl box installation generally takes between 45 minutes to an hour, depending on whether installation is done in a tree or on a gum pole.
Spotted Eagle Owl (Bubo africanus) Box, installed: R1 070.00
Barn Owl (Tyto alba) Box, installed: R1070.00
Spotted Eagle Owl / Barn Owl Box, delivery only: R750.00
Annual Service & Subscription Fee: R640.00
Callout Fee (depending on nature of callout): R200.00 - R500.00
Gum Pole: R290.00
The owl boxes are constructed from recycled plywood which is then weatherproofed with an industrial wood sealant. The thickness of the wood as well as the wood sealant used is designed to give the box an outdoor lifespan of approximately five years or more. Although the box is of a hardy construction an annual maintenance visit is required to re-varnish, replace the substrate, check for signs of wear and monitor occupancy. In occupied boxes, the measuring and ringing of young owls is also undertaken during the service.
The most important component in an owl box is not it's design, it's colour or even it's location. It is the pea gravel substrate within the box. This substrate allows owls to form a ''cup'' in which to lay their eggs and raise their young. Without it, the box is not an owl box - it will not be used by owls and is really just a box high up in your tree.
Why does my owl box need to be serviced annually and the substrate replaced? Owl boxes are designed to replicate a cavity in a tree. Although Johannesburg is well treed, the majority of the trees are alive and unlike dead trees, do not have natural cavities. As a result, your owl box will attract the attention and fill the requirements for many cavity breeding and roosting residents. It is fine for squirrels, Egyptian geese, Genets and other birds to use it out of season. However, these usurpers bring sticks, paper, litter and all sorts of things into the box. Unless these are removed, owls will not utilise your owl box to breed in. Once a year, prior to the owl breeding season, EcoSolutions undertakes to clean out the box and replace the substrate necessary for owl occupation. In addition, your annual service allows us to check that the box is still firmly attached, provide it with a new coat of varnish and make sure that the bee proofing is still intact. Additionally, the service component allows us to seamlessly introduce improved designs, greater expertise and understanding into our programme. If our data reveals that a specific orientation is optimum for successful occupancy, we will implement this during your annual service.
At EcoSolutions, our data is indicating that if you do not commit to the annual management and service of your owl box, you should perhaps carefully consider the purchase of one.
While we are servicing your owl box we are also available to check and replace barbet logs, install bat houses and provide specialised bird food.
The cost for the servicing of your box is R640.00
Probably one of the most frequently asked questions that we receive from prospective and excited clients regarding their new owl box is “How long before we have owls?” 15 years along and this is still a question that we are unable to answer. What we can tell you is based on the 150 plus EcoSolutions owl boxes that are serviced and occupied nationally. We have experienced owls occupying owl boxes within two weeks from the installation date however, this is far from the norm. The large majority of our occupied owl boxes have taken anything from 2 - 5 years before occupancy occurs. That is the reality of it, you could be waiting for 5 years for occupancy to occur; that is if you experience occupancy at all.
The data that we have collected over the course of this project has allowed us to provide you with a blueprint which ensures that everything that can be done to create a viable owl breeding site, has been done. It must be stated that in order for us to collect and interpret data collected through this programme, the unoccupied boxes are just as important to our findings as the occupied ones.
Occupancy trends can be established, areas with low occupancy can be identified and perhaps corrected. It is through the collation of information that this project produces the results that it does. At this stage, one thing that we can say is that our data clearly confirms that the potential occupancy of your owl box is directly related to its annual service and maintenance.
It would be fitting if our data showed a preference by owls for indigenous trees in which to breed. It doesn’t. Pine trees, gum trees, plain trees, oak trees, syringa trees ect. are all suitable for owl box installation. As are many indigenous trees. We have occupied owl boxes in trees, on gum poles and on buildings.
The key to location is more about finding a place that is relatively undisturbed instead of a specific tree or site. Undisturbed is not necessarily a remote tree at the bottom of the garden - owls in urban areas are comfortable with cars, driveways, kids, dogs and cats. Undisturbed really covers direct disturbance. A place where people cannot easily access the box and remove chicks or bang against the box which would cause the owls to leave the box during the day. Disturbing an owl in a breeding box during the day is problematic. The female will often not return to the box until nightfall and consequently, the chicks are left unprotected from crows, cats and other potential predators of small chicks and eggs. In addition, the owlets and eggs, without the female to shield them can be exposed to long periods of sunlight or high winds or afternoon showers. If we have to disturb an owl, for ringing purposes for instance, it is always undertaken at dusk as this allows the female to return to the box quickly once the ringing has been completed.
A quick note on crows - we often hear from concerned clients that they have been told that their EcoSolutions owl box will not attract owls because there is no landing perch. When this programme was initiated (2000 -2001) we included a landing perch on all of our owl boxes. In the first year that we enjoyed occupancy, we lost 3 owl clutches to crows that used the landing perch to scold and frustrate the incubating female owl to the point that she abandoned the box and the chicks and eggs were subsequently predated upon. The 150 occupied owl boxes displayed in our success stories on our website do not have landing perches and produce owlets each year.
The correct orientation of an owl box is always a topic for discussion. It has been said that the box must face south, north, east or west from an “authority” on the topic. Alongside is a graph indicating preference percentages for 60 occupied owl boxes. The graph indicates a strong North (45%) or South (36%) preference. West and East facing boxes appear to be less attractive to owls. We use the word ''appear'' because we are not sure if there aren't numerous variables and biases that contribute to this graph that has nothing to do with an orientation preference.
The majority of houses in the Southern Hemisphere are North facing in order to maximise winter sun and summer shade. When EcoSolutions installs an owl box, we generally face the box towards the home of the client in order for them to see into and monitor the box for occupancy. As a result, these boxes would have a South orientation. In many gardens with North orientated homes, we often place the owl box in the more secluded “back” garden. This would result in the owl house having a North orientation. We very seldom place boxes with the entrance of the box facing away from the house i.e East or West. This may account for the lower occupancy percentage as indicated on the graph. As a consequence of this installation bias, it is almost impossible at this stage to categorically say that there is an orientation preference.
Establishing an orientation preference is still an ongoing undertaking and we are adding data relating to orientation on completion of each owl box service.
EcoSolutions is actively involved in a number of educational programmes. We conduct owl releases at schools and other centres of learning as they are generally perfect sites for owl habitation and at present we have around fifty schools in the greater Gauteng area involved in these projects. Since inception nearly 84 000 children have been involved in the various projects.
We have a few owl release sites at certain private residences and office parks, but in each case the individual or company has to either build an owl release site according to our exact specifications OR have us build the owl release pen for them. The reason for this is that rescued or orphaned owls in captivity and scheduled for release are very strictly controlled and we have to rehabilitate them into the wild.
The owls are tagged and monitored by the University of Cape Town and the process is strictly governed as they need to be monitored and fed in such a way that they can then become free creatures again with minimum risk inflicted on them.
If you wish to have an owl box on your property please note the following:
You must have a tree in your garden that is at least 3-4m in height. The type of tree is not particularly important, but we must be able to get up a tree of that approximate height in order to erect your owl box. If you do not have a tree please inform us prior to installation and we can then erect the owl box on a pole, at an additional fee.
You do not need to be there when we install, but there must be somebody there to let us onto your property.
Domestic cats and dogs pose no threats to owls. Most of our participants have all types of domestic animals and nature tends to live in harmony very nicely. Owls eat mostly rodents and we have not had a single complaint of an owl worrying cats nor vice versa, though we occasionally hear of an owl low-flying over dogs that go sniffing around the bottom of a tree in which owl chicks are nesting. While there is no actual threat to the dogs, when the chicks are on the ground, (as they sometimes are when they are learning to fly), we often advise our members to keep their dogs inside for the 3-4 days that the chicks are on the ground - after that they fly and there is no problem.
Owls will not generally impact on the avian wildlife in your garden. Most garden birds are diurnal, whereas owls are nocturnal, and as such, and they keep a different timetable to the owls and neither interferes with the other.
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