Species specific sampling effort and AI prevalence

This analysis is based on AVHS data from 2006 to 2010. Samples reflect the first capture and sampele of a bird and include 48 birds from 2006, 1540 birds from 2007, 1800 birds form 2008, 809 birds from 2009, and 722 birds from 2010.

The species collected most in the dataset were Mallard (MALL: 2030), Canada goose (CAGO: 1004), Wood duck (WODU: 597), Northern Pintail (NOPI: 392), Gadwall (GADW: 189) Green-winged Teal (AGWT: 114), and American Black Duck (AMDU: 100). Also with sufficient numbers were American Wigeon (AMWI: 82), Ring-necked duck (RNDU: 70), Blue-winged Teal (BWTE: 68), and the Common Goldeneye, (COGO: 59). For all other species, less than 50 individuals were sampled; only speices with more than 5 birds sampled are displayed below.

The figure, below, shows AI prevalence based on pcr from a combined cloacal and oropharyngeal swab sample. Species with the highest AI prevalence were, Blue-winged Teal, Redhead (N = 20), Mallard, Ring-necked duck, Northern Shoveler (N = 18), Green-winged Teal, and Northern Pintail.

Age and sex specific information

Detection of AI by shedding is thought to occur during an animals first exposure to infection before the development of protective antibodies. I expect age-specific detection patterns in both females (red) and males (blue). Age categories are Local (L), Hatch Year (HY), and After Hatch Year (AHY; > 1). Local designates a young bird known to have hatched during that year that incapable of sustained flight. Hatch year designateds a bird capable of sustained flight still less than one year old. After hatch year refers to all older individual. Note t

Mallard and Canada Goose

Wood duck and Northern Pintail

Gadwall and Green-winged Teal

Ring-necked duck and American Black Duck

Blue-winged Teal and American Wigeon

Now with H5 and H7

Overall

For Mallards, Northern Pintail; Green-winged Teal; American Black Duck(?); Blue-winged teal; American Wigeon

Other species are not displayed when prevalence of H5 or H7 is less than 1%. Canada Goose (H5 prev = 0.001, H7 prev = 0); Wood duck (H5 prev = 0.007, H7 = 0.002); Gadw (H5 = 0.005; H7 = 0); Rndu (H5 = 0; H7 = 0);

Seasonal information in the AVHS dataset

Plots of monthly sampling and prevalence show that most sampling occured between June and October. Prevalence is also highest at those times, but this could be due to sampling effort. There is a low, but non-zero prevalence in Northern Pintail and Mallards prevalence outside this sampling window.

Spatial information in the AVHS dataset