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External Examination of Seabirds: Plumage & Morphometrics

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External Examination of Seabirds: Plumage & Morphometrics Quantitative analysis of form, encompasses size and shape Seabird Topography ➢ Naming Conventions: • Parts of the body • Types of feathers (Harrison 1983) Types of Feathers Coverts: Rows bordering and overlaying the edges of the tail and wings on both the lower and upper sides of the body. Help streamline shape of the wings and tail and provide the bird with insulation. Feather Tracks ➢ Feathers are not attached randomly. • They occur in linear tracts called pterylae. • Spaces on bird's body without feather tracts are called apteria. • Densest area for feather tracks is head and neck. • Feathers arranged in distinct layers: contour feathers overlay down. Generic Pterylae Types of Feathers Contour feathers: outermost feathers. Define the color and shape of the bird. Contour feathers lie on top of each other, like shingles on a roof. Shed water, keeping body dry and insulated. Each contour feather controlled by specialized muscles which control their position, allowing the bird to keep the feathers in clean and neat condition. Specialized contour feathers used for flight: delineate outline of wings and tail. Types of Feathers Flight feathers – special contour feathers Define outline of wings and tail Long and stiff Asymmetrical those on wings are called remiges (singular remex) those on tail are called retrices (singular retrix) Types of Flight Feathers Remiges: Largest contour feathers (primaries / secondaries) Responsible for supporting bird during flight. Attached by ligaments or directly to the wing bone. Types of Flight Feathers Flight feathers – special contour feathers Rectrices: tail feathers provide flight stability and control. Connected to each other by ligaments, with only the inner- most feathers attached to bone. Naming Convention: Retrices and Remiges Primaries: count down from outer-most (p10, p9, … p1) Secondaries: count up from outer-most (s1, s2, … s10) Retrices: count up from one side of the tail (either one) (Pyle 2008) Wing Topography Quantitative analysis of form – Naming Conventions What Wing Feathers do you need to Know ? Primaries, Secondaries, Coverts, Tertials, Scapulars Scapulars: Small feathers on the shoulder. In flight, located at base of wing's leading edge. Tertials: Protective cover for folded primaries and secondaries; Not true flight feathers because they are not attached to wing bone. Feather Topography Stiff central shaft runs A Typical Wing Feather: entire length of feather. Consists of 2 distinct sections: The calamus is the part of the shaft closest to the bird's body. It is hollow and without any vanes. The rachis is the distal end of the shaft. The rachis is solid and is defined as the area to Note the assymmetry of the which vanes are attached. vanes: outer vs. inner Feather Topography Vanes extend from each side of the feather. Series of parallel branches called barbs make up vane. Series of branchlets (barbules) extend from the barbs. Tiny hooklets tie the barbules and barbs together. This architecture makes feathers strong and light. Types of Feathers The shape and stiffness of the feathers are driven by its uses: - Insulation (down and semiplumes) - Flight (tail and wings) - Mechanoreception (filoplumes, bristles) Tail Feathers Naming Conventions • Types of tails Streamers in RTTR (Harrison 1983) Types of Feathers Down: for keeping birds warm. Rachis either missing completely or substantially reduced in length. Barbules lack hooks. Results in very soft and fluffy feather. Without hooks, barbs and barbules create insulating air pockets. Natal downs are present on well developed hatchlings that can almost immediately walk or swim. Other chicks, which save energy by not producing down, are able to absorb the body heat of parent bird more easily. Altricial Precocial Down in Adult Birds Breeding birds develop a brood patch of down: Number and position depends on number of eggs in the species … and their phylogeny. Brood patch can range from exposed skin (no feathers), to regrown down to fully feathered Wing Topography Primaries: connected to manus (bird's "hand“), consisting of the carpometacarpus and the phalanges; longest and narrowest of the remiges (especially ones attached to phalanges), and can be individually rotated. Secondaries: connected to the ulna. Secondary feathers remain close together in flight (cannot be individually separated like primaries) and help to provide lift by creating airfoil shape of the bird's wing. Wing Osteology Arm section 1. Upper arm – humerus 2. Sesamoid bone 3. Lower arm - ulna 4. Lower arm - radius Hand section (manus) 5. Wrist - radiale and ulnare 6. Metacarpal - carpometacarpus 7. Thumb - alula 8. Digits - phalanges Wing Osteology Find these parts in your bird : elbow wrist thumb The Alula - or winglet Bird’s thumb is covered by very stiff and short feathers, called the alular quills Introduction to Morphometrics Lab Standardized measuring and recording of data www.pelagicos.net/pdfs/necropsy/AlterraRapport_0672_withcover.pdf Species Identifications 99: FFSH (P. carneipes) 101a, b: WTSH (P. pacificus) 103: SOSH (P. griseus) 104: STSH (P. tenuirostris) (Harrison 1983) External Features (Harrison 1987) External Features Diagnostics: • Size • Color • Jizz: “feeling the bird gives you when you see it” (Harrison 1983) Introduction to Seabird Necropsies • Each student will measure / record data for one bird • Turn in the form to instructor at the end of class • NOTE: do not put cotton ball in bird’s mouth until you take the bill measurements Necropsies – External Observations 1) Noting and recording the condition of your specimen Check for the following: • Completeness / Freshness • Trauma: bleeding • Entanglement / Oiling Record Information on Sheet: Necropsies – External Observations Why do we record freshness ? NOTE: score can be changed once we open up the bird Necropsies – External Observations Why do we record completeness ? NOTE: we only necropsy complete (CC code) birds Necropsies – External Observations 2) Examining and recording plumage of your specimen: Check for the following: • Color Morph (light / dark) • Molt (wings / tail) • Down (ventral / dorsal) • Incubation patch, P9 vs P10 Record Information on Sheet: Necropsies – External Observations Score each primary feather from the left and right wings Score the tail, from one end to the other (Note: 12 retrices) Check for brood patch and for external molt (body / secondaries) Necropsies – External Observations • Evidence of Molting: Pin feathers, Abnormal feathers Body Molt Tail Molt Necropsies – External Observations • Evidence of Molting: Waxy sheath covering feather Wing Molt Tail Molt Necropsies – External Observations • Examples of Brood Patches: Ranging from bare skin to fully feathered (regrown or nor present) Bare Downy NOTE: Record Estimate % of down, bare skin and feathers Necropsies – External Observations 3) Get “measurements” of your bird – Sarah D. & David: Measure the following: • Culmen length / depth • Wing length (relaxed) • Tarsus length • Head length • Mass (in grams) NOTE: use metric system Record Information on Sheet: Necropsies – External Observations • Making Seabird Morphometrics Measurements NOTE: For wing chord, note if wing is fully grown (P10 > P9). Check right and left wings and record P10/P9 score on sheet, as follows: P10 > P9: code of “3” P10 = P9: code of “2” P10 < P9: code of “1” Necropsies – External Observations • How to Make Bird Morphometrics Measurements NOTE: we are only making measurements A, not B Necropsies – External Observations Note: Before You are done: Transcribe information from tag ID onto necropsy sheet (Note: Keep id tag with the bird on the tray) • Necropsy Date: 09 – 21 – 2018 • Species: WTSH (Wedge-Tailed Shearwater) • Collection number: YYYY – NNN (year and specimen number) • Dissected By: YOUR NAME • Finder: “SLP” (sea life park) • Country / Location / Date: • Other Comments: cause of death, trauma (?) Necropsies – External Observations Once your data sheet is complete and checked out: • Place cotton ball in bird’s mouth • Bag your bird • Staple ID in outside of the bag • Place in “dead bird” tub Next week we will get into the birds… Bring closed – toed shoes. Bring own lab coat, if you have one. Necropsies – Preparing Vials For each bird, we have two cryovials and two bags: ➢ 2 Cryovials for isotopes: Muscle / Liver • Label with pen on blue painter’s tape • Write down Bird ID and tissue: Liver OR Muscle ➢ 2 Whirl Packs: Feathers / Isotopes • Label whirl pack with black sharpie • Add piece of write-in-the-rain paper • Write down Bird ID and: ”Isotopes” OR “Feathers” ➢ Take 4 – 5 breast feathers, place in “feather bag” ➢ Place “feather bag” into “isotope bag” ➢ Place cryovials into “isotope bag” Making Wing Measurements ➢ Weight (to the closest gram): ➢ Lay out bird on its back and stretch the wings out. Making Wing Measurements Inside of the wing outline, write the following: - Bird ID (WTSH 2017-100) - Bird Mass (to the closest gram).
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