Split Bird Rings

Porzana makes a full range of split bird rings from sizes 2.0 mm diameter to 22.0 mm, plus clip rings and special rings for Guillemot, Razorbill and others. Rings for use on smaller, short-lived species are made from a magnesium-aluminium alloy, and incoloy (a nickel-chromium alloy) is used for most large, long-lived species and where excessive abrasion or exposure to saline or alkaline water would shorten ring life. For cost reasons, stainless steel is used for rings with a diameter greater than 12.5 mm. Although incoloy is a more expensive metal, it is more durable than stainless steel and is also preferred by our customers due to its better handling qualities, the rings being easier to close and less susceptible to ‘spring-back’ than pure steel. Most of our aluminium alloy rings are ‘C’ shaped, whereas the harder incoloy and steel rings are ‘V’ shaped for easier and better closing.

The table below shows the standard ring sizes produced, along with the equivalent British Trust for Ornithology (BTO), Australian Bird and Bat Banding Scheme (ABBBS) and US Fisheries and Wildlife Service (USFWS) reference codes. The internal diameter is the diameter of the ring when closed.

Non standard products

Although the standard list of products should cover most requirements, special orders for unusual ring sizes, shapes or numbering requirements can also be considered on request. In recent months these special orders have included field-readable rings for Puffin, Greater Flamingo, Roseate Tern and Blue-footed Booby.

For full pricing information and quotes please contact Shane Muggridge (porzana@bto.org)

Equipment

Porzana also supplies a range of specialised pliers designed for use with our rings (see Equipment). The BTO Ringers’ Manual includes a useful section on closing rings. Available on request as a PDF.

Internal Diameter BTO Ref ABBBS Ref USFWS Ref Metal Height & Gauge Ring Shape Number Height Rings per Packet
2.0 mm AA 01 0A 5.5 x 0.38 mm C 1.6 mm 100
2.3 mm A 02 1 5.5 x 0.38 mm C 1.6 mm 100
2.8 mm B 03 1B 5.5 x 0.50 mm C 1.6 mm 100
3.3 mm 04 1A 5.5 x 0.50 mm V 1.6 mm 100
3.5 mm CC 1D 5.5 x 0.50 mm V 1.6 mm 100
4.0 mm 05 2 5.5 x 0.50 mm V 1.6 mm 100
4.3 mm C 2A 7.0 x 0.60 mm V 1.6 mm 100
4.5 mm 06 7.0 x 0.60 mm V 1.6 mm 100
5.25 mm D 3B 7.0 x 0.60 mm V 1.6 mm 100
2.5/4.0 mm SO K 4.0 x 0.38 mm 1.6 mm 50
Internal Diameter BTO Ref ABBBS Ref USFWS Ref Metal Height & Gauge Ring Shape Number Height Rings per Packet
2.3 mm A2 1 5.5 x 0.35 mm V 1.6 mm 100
2.8 mm B2 03 1B 5.5 x 0.35 mm V 1.6 mm 100
3.3 mm B+ 04 1A 5.5 x 0.35 mm V 1.6 mm 100
4.0 mm 05 2 5.5 x 0.35 mm V 1.6 mm 100
4.3 mm C2 2A 5.5 x 0.35 mm V 1.6 mm 100
4.5 mm 06 5.5 x 0.35 mm V 1.6 mm 100
4.75 mm 3 5.5 x 0.35 mm V 1.6 mm 100
5.25 mm D2 3B 7.0 x 0.56 mm V 2.4 mm 100
5.5 mm 07 3A 7.0 x 0.56 mm V 2.4 mm 100
6.35mm 4 7.0 x 0.56 mm V 2.4 mm 100
7.0 mm Esp 4A 7.0 x 0.56 mm V 2.4 mm 50 or 100
8.0 mm 5 9.0 x 0.85 mm V 3.2 mm 50 or 100
9.0 mm FV 9.0 x 0.85 mm V 3.2 mm 50 or 100
9.5 mm 6 9.0 x 0.85 mm V 3.2 mm 50 or 100
11.0 mm G 7A 9.0 x 0.85 mm V 3.2 mm 50 or 100
12.5 mm H 7 9.0 x 0.85 mm V 3.2 mm 50
9.0 mm FC 8.7 x 0.60 mm C 3.2 mm 50
Razorbill Raz 5R 9.0 x 0.85 mm 3.2 mm 50
Guillemot Guil 6M 9.0 x 0.85 mm 3.2 mm 50
16.0 mm 8.7 x 0.60 mm Clip 3.2 mm 10
19.0 mm 8.7 x 0.60 mm Clip 3.2 mm 10
22.0 mm 8.7 x 0.60 mm Clip 3.2 mm 10
26.0 mm M. Inc 8.7 x 0.60 mm Clip 3.2 mm 10
Internal Diameter BTO Ref ABBBS Ref USFWS Ref Metal Height & Gauge Ring Shape Number Height Rings per Packet
11.0 mm GG 11 7A 12.0 x 1.00 mm V 3.2 mm 50
12.5 mm 27 7 12.0 x 1.00 mm V 3.2 mm 50
14.0 mm J 12 7B 12.0 x 1.00 mm V 3.2 mm 50
16.0 mm K 13 7D 12.0 x 1.00 mm V 3.2 mm 50
18.0 mm 28 8 12.0 x 1.00 mm V 3.2 mm 50
19.0 mm L 14 12.0 x 1.00 mm V 3.2 mm 50
22.0 mm 15 9 12.0 x 1.00 mm V 3.2 mm 50
26.0 mm Mb 15 9 12.0 x 1.00 mm Clip 3.2 mm 10

Addresses and Numbering

Although a few customers require just a simple number to be stamped on the rings, most also require an address. The amount of information that can be stamped on a ring is dependent on the size of the ring, and the table below describes the limits. For example a 2.0 mm diameter ring can have two lines of address each with a maximum of nine characters plus a six character number. Typically the number will comprise of a one or two character prefix and then the number (e.g. A00001 or AB0001). It should be emphasised that these are the maximum characters and numbers that can be shown on the ring, and for clarity it is advisable to keep the address and numbering system as simple as possible.

 

Address Die Numerator
Internal Diameter Metal Height Max Lines Max Characters Max Height Number Size Max Digits
Alloy Rings Die 1 2.0 mm 5.5 mm 2 9 1.0 1.6 6
Die 2 2.3-2.8 mm 5.5 mm 2 11 1.0 1.6 7
Die 3 3.3-5.25 mm 5.5 & 7.0 mm 2 16 1.0 1.6 7
Die 4 2.5-4.0 mm 4.0 mm 1 11 1.0 1.6 7
Incoloy & Stainless Steel Rings Die 5 2.3-2.8 mm 5.5 mm 2 11 1.0 1.6 7
Die 6 3.3-4.75 mm 5.5 & 7.0 mm 2 16 1.0 1.6 7
Die 7 5.25-7.0 mm 7.0 mm 2 23 1.25 2.4 7
Die 8 8.0-12.5 mm 8.7 & 9.0 mm 2 28 1.75 3.2 7
Die 9 14.0-22.0 mm 12.0 x 1.00 mm 2 36+ 2.5 3.2 7

The standard numerator used on 8.0 mm rings and above is 3.2 mm in height but a larger 5.0 mm numerator can be used on the wider stainless steel rings of 11.0 mm diameter upwards on request, however this numerator has a maximum of five digits.

To cover the complete range of ring sizes a total of nine address dies is optimal, although smaller dies can be used on larger rings of the same metal type (for example a die made for a 5.25 mm incoloy ring could be used on a 12.5 mm incoloy ring). The manufacture of address dies has to be subcontracted to a specialist engraving company but a quotation for the cost of producing these dies can be obtained on request. The dies are retained at the factory for future orders.

New customers deciding on a numbering scheme should give careful consideration to the number of characters that they wish to use, and whether they wish to differentiate between the various ring sizes by using prefixes. It is advisable to avoid the use of characters that are easily confused with similar letters or numbers, for example if ‘E’ is used then ‘F’ should be avoided, or if ‘C’ is used then ‘G’ should be avoided. On smaller rings, suggested letters to avoid are: F, G, I, M, O, Q, S, U, W and Z wherever possible.