# Tag Harness Sizes

This table lists harness sizes for the pre-fabricated ‘figure eight’ leg loop harness method based on real sizes used on individuals tagged in the field. Sizes include the length of the entire single leg-loop, but do not include overlap with the tag. Weights can be used to help specify which harness size to use.

Please note that these are guidelines. Regardless of what sizes you find here, the harness should always be fitted to the individual. Please see a [**How to Tag Animals**](https://docs.motus.org/tagguide/tag-deployment#how-to-tag-animals) for more information.

This table lists harness sizes for the pre-fabricated ‘figure eight’ leg loop harness method based on real sizes used on individuals tagged in the field. Sizes include the length of a single leg-loop, not include overlap with the tag. Weights can be used to help specify which harness size to use.

<figure><img src="/files/jd5PE95Pp77b9wWWhhhM" alt=""><figcaption><p>Example tag harness measured to 28mm, not including the tag width of 4mm.</p></figcaption></figure>

Please note that these are guidelines. Regardless of what sizes you find here, the harness should always be fitted to the individual. Please see a [**How to Tag Animals**](#how-to-tag-animals) for more information.

| Species                        | Harness Size (mm) | Weight (g) | Sample size |
| ------------------------------ | ----------------- | ---------- | ----------- |
| Yellow-billed Cuckoo           | 50-61             | 43-80      | 10          |
| Black-billed Cuckoo            | 52                | 34         | 1           |
| Hammond's Flycatcher           | 29                | 9.5        | 1           |
| Dusky Flycatcher               | 34                | ?          | 1           |
| Say's Phoebe                   | 37                | 23.5       | 1           |
| White-eyed Vireo               | 28-34             | 9-12       | 5           |
| Warbling Vireo                 | 33-35             | 13-14      | 3           |
| Red-eyed Vireo                 | 39-42             | 15-20      | 100+        |
| Bank Swallow                   | 32-34             | 10-13      | 50+         |
| Barn Swallow                   | 34-37             | 17-19      | 80+         |
| House Wren                     | 33                | 11         | 1           |
| Eurasian Reed Warbler          | 30                | 9-13       | 60+         |
| Gray-cheeked Thrush            | 50-54             | 26-37      | 30+         |
| Bicknell's Thrush              | 46-50             | 24-30      | 12          |
| Swainson's Thrush              | 48-52             | 25-36      | 100+        |
| Brown Thrasher                 | 62                | 67         | 1           |
| Golden-winged Warbler          | 29                | 8          | 1           |
| Orange-crowned Warbler         | 29-32             | 8-10       | 4           |
| Kentucky Warbler               | 34-35             | 12-15      | 2           |
| Hooded Warbler                 | 30-34             | 9-14       | 4           |
| Magnolia Warbler               | 24-28             | ?          | ?           |
| Blackpoll Warbler              | 33-36             | 10-22      | 200+        |
| Black-throated Blue Warbler    | 26-28             | ?          | ?           |
| Palm Warbler                   | 26-34             | 9-12       | 5           |
| Yellow-rumped Warbler (Myrtle) | 31-34             | 10-15      | 100+        |
| Prairie Warbler                | 26-29             | 7-10       | 7           |
| Canada Warbler                 | 34                | 10-12      | ?           |
| Yellow-breasted Chat           | 40-42             | 22-25      | 4           |
| Saltmarsh Sparrow              | 36-39             | 18-20      | 60+         |
| Clay-colored Sparrow           | 30-31             | 9-12       | 7           |
| Field Sparrow                  | 30-32             | 12-13      | 6           |
| Lark Sparrow                   | 32-42             | 20-28      | 1           |
| Fox Sparrow                    | 48-50             | 37-44      | 20          |
| White-crowned Sparrow          | 44                | 31         | 1           |
| White-throated Sparrow         | 45-50             | 23-31      | 100+        |
| Savannah Sparrow (Typical)     | 38-40             | 20-25      | 84          |
| Savannah Sparrow (Ipswich)     | 38-44             | 21-30      | 100+        |
| Eastern Towhee                 | 50                | 40         | 1           |
| Summer Tanager                 | 39-40             | 26-27      | 2           |
| Blue Grosbeak                  | 37                | 26         | 1           |
| Indigo Bunting                 | 34-36             | 14-17      | 10          |
| Painted Bunting                | 34                | ?          | 1           |
| Dickcissel                     | 38-44             | 22-32      | 3           |
| Orchard Oriole                 | 40-42             | 19-22      | 2           |
| Cerulean Warbler               | 26-28             | ?          | ?           |


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