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Information sheetWildlife ManagementOsprey nest platform manualThe purpose of this document is to provide information to proponents undertaking nest relocation or surrogate nestconstruction for Osprey species under an DES permit or authority.Artificial nesting platforms for Eastern OspreysFew birds can compete with the osprey when it comes to attracting attention and affection from the generalpublic. This is largely due to their habit of using the same (often massive) nest year after year, their strikingappearance and their hunting prowess – using their talons to snatch fish from the water in spectacular fashion.Due the osprey’s widespread distribution along the Queensland coastal strip, this information sheet will beapplicable to other regions even though it is largely based on information from south-east Queensland.Around the Gold Coast region, there are 14 historic osprey nests sites (refer to map 1). They often use trees fornesting platforms as well as man-made structures, such as power poles. Due to public safety issues and thesafety of the bird and its chicks, the choice of nesting sites is not always appropriate. Old trees with largebranches may pose a danger to the public and, in some cases, may need to be removed. Nests built on powerpoles may be flimsy and not sturdy enough to support the eggs and chicks. These birds also run the risk ofbeing electrocuted and nesting material can even cause power failures.Map 1: Historical known osprey nest sites in the Gold Coast area.Page 1 of 6 NCS/2016/3186 Version 1.00 Effective: 23 SEP 2016ABN 46 640 294 485

Information sheetOsprey nest platform manualIn these situations, there is the option of constructing an artificial alternative nesting platform for the birds. Dueto their preference for nesting in exposed situations, ospreys provide a unique opportunity to relocate the nest toelevated platforms where they can successfully breed and raise their young.This information sheet contains general information on ospreys, as well as specific information on therequirements for building an artificial platform to ensure that the ospreys have a suitable nesting site.Construction diagrams and the materials required are also included.IdentificationOspreys are raptors (birds of prey) with a body length of 50–63 cm and a wingspan of up to 170 cm. They havedark brown upperparts, with a white head and underparts. They also have a brown streak through the eye,down the sides of the neck and a brown “necklace” across its chest. This “necklace” is darker and morepronounced in the female. Juveniles have a darker face and heavier bands across the chest than adults, and amore mottled appearance. Adult females are slightly larger than the males 3. In flight, ospreys soar on long,arched wings which have a characteristic bend at the “wrist” joint 1. The tail is short and square with a whiteedge on the tip 3.HabitatEastern ospreys are commonly found in estuarine and marine areas, keeping to the coast and large river inlets.They have been recorded in habitats ranging from mangroves, inshore seas, coastal islands, estuaries andrivers 5.DietOspreys feed almost exclusively on fish of up to 2 kg in size. They are also known to occasionally take seasnakes. The birds usually feed singly or in dispersed pairs within their breeding and feeding territory, whichgenerally consists of 5–20 km of coastline 4. The osprey hovers above the water, then dives from a height of 10–40 m and plunges feet first into the water 1. Gripping fish with their talons, the catch is then carried headfirst toreduce wind resistance, back to a roost or perch before being ripped apart and eaten. To assist in holding on tothe slippery fish, the feet have spiny footpads called spicules. Osprey are very effective and efficient hunters,with approximately 90% of their dives successfully resulting in a catch 4.Osprey (Pandion spp.) feeding, Moreton Bay, EPA 2000.Page 2 of 6 NCS/2016/3186 Version 1.00 Effective: 23 SEP 2016Department of Environment and Science

Information sheetOsprey nest platform manualBreedingBreeding occurs from June to September. Nesting pairs of osprey perform courtship aerial dives and swoops ata height of 100–300m above the nest site. Copulation usually occurs on the nest or close to it. Calls are madeduring displays but are infrequent at other times 4. Ospreys typically mate for life, returning to the same nestover and over again.NestingIn south-east Queensland, ospreys start nesting around April. Large nests are built from sticks and lined withseaweed and grass. The nests may be constructed on cliff faces, headlands, rocky foreshores and islands andin the forks of large trees up to 30 m above the ground 4. The nests are generally located within 3 km of a waterbody and frequently within sight of water 1. Ospreys are also known to nest on man-made structures, such ascommunication towers, power poles, channel markers and artificial nest platforms. Studies indicate that ospreysare successful in raising young on such structures1.Nests may be used for consecutive years, with the pair adding material to the nest year after year. Both thefemale and male help to build and repair the nest, with the male collecting most of the material and the femaleworking it into the nest structure. Usually 2–3 matt white to buff-brown speckled eggs are laid once a year.Generally the female incubates the eggs for about 5 weeks while the male brings her fish. The young developfeathers at about 30 days of age. The male collects fish for the brood with the female tearing up the fish intosmall pieces to feed to the young. The young are fed until they leave the nest, approximately 8 weeks afterhatching 4.The young continue to use the nest for roosting for about a week after fledging. Within this time they are taughtor learn how to fish. For several weeks after this time, the young birds continue to use the nest as a feedingplatform 4. The young are sexually mature at approximately 3 years. The chance of survival between each yeardoes vary, however, juvenile ospreys have an average survival rate of approximately 60% and adult ospreys 80to 90%. The oldest known osprey in the wild was 25 years old, however, very few individuals reach this age 1.Osprey (Pandion spp.) nest, in fork of tree, Coomera, Gold Coast, EPA 2000.Page 3 of 6 NCS/2016/3186 Version 1.00 Effective: 23 SEP 2016Department of Environment and Science

Information sheetOsprey nest platform manualNesting platformsConstructionWhen creating an artificial nesting platform, special consideration must be given to the suitability of the location.As the main dietary component of the osprey is fish, platforms must be located close to water. Ideally the siteshould be 50 m from the water body with a maximum distance of 3 km 2. As predation is a concern for theospreys, the platform should also be erected in an open area to allow for an unobstructed view of the sky. Theheight of the platform should also be greater than any nearby trees. If several nesting platforms are to be built inthe one location, they should be placed at no less than 300 m apart 2.To build a nesting platform the materials listed on page 5 are required. Plans for the construction of the platformare also attached. Please note that all timber must be treated and all the fixings must be galvanised.These plans are for the construction of a timber platform, however there is the option of creating a steel platforminstead.Osprey nesting platform – This design has since beenrevised to remove the vertical perch as crows werefound to use the roost to harass the osprey for food,EPA 2000.Osprey nesting platform – Nesting platform atCurrumbin Creek, EPA 2000.MaintenanceThe nesting platforms require an inspection at least once a year 2. During this inspection, any foreign, potentiallyharmful material – such as fishing line, plastic bags and fishing hooks – should be removed. A layer of sticks canalso be removed if the material in the nest is greater than half a metre deep. As the ospreys continually addmaterial to their nest each year, nests that become too large may be blown off the platform by strong winds 2.Page 4 of 6 NCS/2016/3186 Version 1.00 Effective: 23 SEP 2016Department of Environment and Science

Information sheetOsprey nest platform manualOsprey nest platform material requirementsHardwood treated timber requirementsAll timber to be treatedItemMain Pole FloorMain Floor SupportsFloor End SupportsFlooringHorizontal PerchAngle BraceSize (mm)75 x 75 x 140075 x 75 x 180075 x 75 x 1000100 x 50 x 100065 x 100 x 1800100 x 50 x 670Metal work requirementsAll metal work to be hot dip galvanisedItemGalv Ring Shanked NailsGalv Ring Shanked NailsTriple Grip Timber BracesBracing StrapCup Head Bolts, Washers & NutsCup Head Bolts, Washers & NutsCup Head Bolts, Washers & NutsCup Head Bolts, Washers & NutsCup Head Bolts, Washers & NutsMain Support King BoltSize75 mm25 mmAs required25 mm x 0.5 x 1400M10 x 235M10 x 160M10 x 125M10 x 110M10 x 130M20 x 430 Check Pole Head on SiteQuantity222721QuantityAs requiredAs required402482441Pole requirements 20/8KN CCA Treated Hardwood Timber Pole Sink Pole 3.0 m Install Maximum Depth Concrete Foundation Require 20 Bags of Premix, Easymix 20 Kg Bag Pole Steps Galv Steel 16 mm Dia Require 18 Aluminium Pole Cap Approx. 355 x 0.4 mmPlease Note: The vertical perch was removed from the materials list as crows were found to be using this upperroost.Osprey camera informationThe installation of osprey cams allow for the remote monitoring of nest sites and chick development. A camerathat has motion sensors, is waterproof and has infrared capabilities for night-time observations is ideal. A varietyof cameras exist that are suitable for observing the ospreys. At the higher end of the market is the camera suchas that which was used for the “Frodocam”, which monitors Peregrine Falcons in Brisbane. This site createsworldwide interest, and provides an excellent educational opportunity regarding the conservation of raptors.The costs of setting up an osprey webcam vary greatly, depending on the features of the camera.Page 5 of 6 NCS/2016/3186 Version 1.00 Effective: 23 SEP 2016Department of Environment and Science

Information sheetOsprey nest platform manualReferences1. Kirschbaum, K., 2000, Pandion haliaetus (Online) World Wide Web. Accessed 21st Sept counts/information/Pandion haliaetus.html.2. Land Owner Resource Centre, 1999, Building Nesting Platforms for Ospreys. (Online) World Wide Web.Accessed 21st Sept 2016: http://Irconline.com/Extension Notes English/pdf/ospry.pdf.3. Queensland Museum, 1995, Wildlife of Greater Brisbane. Queensland Museum, Brisbane.4. Reader’s Digest, 1986, Complete Book of Australian Birds, 2nd Edition. Reader’s Digest, Sydney.5. Simpson, K. and Day, N., 1999, Field Guide to the Birds of Australia, 6th Edition. Penguin Books,Victoria.Disclaimer: While this document has been prepared with care it contains general information and does not profess to offerlegal, professional or commercial advice. The Queensland Government accepts no liability for any external decisions oractions taken on the basis of this document. Persons external to the Department of Environment and Science should satisfythemselves independently and by consulting their own professional advisors before embarking on any proposed course ofaction.Approved:Enquiries:RD WilliamsA/Executive Director, NCS23/09/2016Wildlife n historyVersionEffective dateComments1.0023 September 2016Approved by RD Williams, 23/09/2016Page 6 of 6 NCS/2016/3186 Version 1.00 Effective: 23 SEP 2016Department of Environment and Science