Table 2. Numbers of individuals collected in pre and post irrigation periods for focal species and their AI values.
The final numeric column presents AI ratios, with increases indicated by positive numbers and decreases indicated by negative numbers (see text for details).
| Early collecting | Recent collecting | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Species | May | Jun | Jul | Aug | Total | AI | May | Jun | Jul | Aug | Total | AI | AI change | Notes on potential collecting bias |
| Decrease predicted | ||||||||||||||
| Aimophila carpalis | 9 | 9 | 1 | 19 | 1.57 | 3 | 10 | 7 | 20 | 2.25 | 1.44 | |||
| Auriparus flaviceps | 8 | 6 | 1 | 15 | 1.24 | 2 | 10 | 2 | 14 | 1.58 | 1.28 | |||
| Campylorhynchus brunneicapillus | 2 | 4 | 1 | 7 | 0.58 | 1 | 1 | 2 | 7 | 10 | 1.13 | 1.95 | ||
| Colaptes chrysoides | 5 | 8 | 2 | 1 | 16 | 1.32 | 1 | 2 | 3 | 0.34 | −3.90 | |||
| Geococcyx californianus | 2 | 5 | 1 | 8 | 0.66 | 1 | 1 | 2 | 0.23 | −2.87 | ||||
| Passerina versicolor | 7 | 10 | 1 | 18 | 1.48 | 3 | 13 | 16 | 2 | 31 | 3.49 | 2.36 | Breeds in thorn scrub but abundant forager in weedy edges. | |
| Pheucticus chrysopeplus | 12 | 12 | 0.99 | 1 | 1 | 0.11 | −8.77 | |||||||
| Pipilo fuscus | 3 | 4 | 7 | 0.58 | 2 | 2 | 0.23 | −2.56 | ||||||
| Polioptila melanura/nigriceps | 6 | 7 | 0 | 4 | 17 | 1.40 | 8 | 5 | 13 | 1.47 | 1.05 | |||
| Totals/Mean AI values | 119 | 1.09 | 96 | 1.20 | 1.02 | |||||||||
| Increase predicted | ||||||||||||||
| Agelaius phoeniceus | 1 | 1 | 0.08 | 2 | 2 | 2 | 0.23 | 2.74 | Abundant breeder in cattails where we seldom collected | |||||
| Cacicus melanicterus | 27 | 27 | 2.23 | 4 | 1 | 5 | 0.56 | −3.95 | Under sampled with nets. The 27 early specimens were taken in June 2004 at a single locality. | |||||
| Calocitta colliei | 1 | 6 | 7 | 0.58 | 2 | 2 | 4 | 0.45 | −1.28 | Under sampled with nets. | ||||
| Coccyzus americanus | 3 | 3 | 0.25 | 12 | 1 | 13 | 1.47 | 5.93 | Settles in late June, breeds Jul–Aug. The three early specimens, taken 9, 14, 22 Jun, are likely migrants. | |||||
| Corvus sinaloae | 8 | 10 | 1 | 4 | 23 | 1.90 | 1 | 5 | 7 | 13 | 1.47 | −1.29 | Under sampled with nets. | |
| Crotophaga sulcirostris | 1 | 7 | 2 | 8 | 18 | 1.48 | 8 | 3 | 11 | 1.24 | −1.20 | |||
| Geothlypis trichas | 6 | 7 | 13 | 1.07 | 1 | 1 | 1 | 3 | 0.34 | −3.17 | Common near coast where we seldom collected. | |||
| Hirundo pyrrhonota | 3 | 1 | 4 | 0.33 | 6 | 3 | 2 | 11 | 1.24 | 3.76 | Large colonies under most bridges. | |||
| Icteria virens | 5 | 10 | 4 | 19 | 1.57 | 14 | 12 | 26 | 2.93 | 1.87 | Common in brushy edges. | |||
| Icterus pustulatus | 18 | 1 | 19 | 1.57 | 6 | 6 | 8 | 20 | 2.25 | 1.44 | ||||
| Icterus spurius | 4 | 1 | 5 | 0.41 | 1 | 26 | 4 | 31 | 3.49 | 8.48 | Now an abundant breeder. | |||
| Melospiza melodia | 2 | 2 | 0.16 | 1 | 2 | 4 | 6 | 0.68 | 4.10 | Common along coastal canals. | ||||
| Mimus polyglottos | 1 | 1 | 0.08 | 3 | 4 | 5 | 9 | 1.01 | 12.31 | Now an abundant breeder in ecotones. | ||||
| Molothrus aeneus | 9 | 8 | 1 | 2 | 20 | 1.65 | 5 | 4 | 9 | 1.01 | −1.62 | |||
| Molothrus ater | 3 | 4 | 1 | 8 | 0.66 | 1 | 3 | 9 | 13 | 1.47 | 2.22 | August increase could be birds moving in to exploit late breeding hosts. | ||
| Myiarchus tyrannulus | 13 | 9 | 22 | 1.81 | 4 | 3 | 5 | 12 | 1.35 | −1.34 | Under sampled with nets. | |||
| Myiodynastes luteiventris | 5 | 5 | 0.41 | 1 | 1 | 0.11 | −3.66 | Under sampled with nets. | ||||||
| Myiozetetes similis | 7 | 8 | 4 | 19 | 1.57 | 2 | 4 | 6 | 0.68 | −2.32 | Under sampled with nets. | |||
| Pachyramphus aglaiae | 8 | 12 | 6 | 26 | 2.14 | 4 | 4 | 0.45 | −4.75 | Under sampled with nets. | ||||
| Pitangus sulphuratus | 4 | 6 | 1 | 3 | 14 | 1.15 | 1 | 5 | 6 | 0.68 | −1.71 | Under sampled with nets. | ||
| Quiscalus mexicanus | 4 | 7 | 3 | 14 | 1.15 | 7 | 8 | 16 | 7 | 31 | 3.49 | 3.03 | Many nesting colonies near canals close to coast. | |
| Saltator coerulescens | 4 | 4 | 5 | 13 | 1.07 | 4 | 6 | 10 | 1.13 | 1.05 | ||||
| Sayornis nigricans | 2 | 2 | 0.16 | 3 | 2 | 5 | 0.56 | 3.42 | Under sampled with nets. Common along canals. | |||||
| Stelgidopteryx serripennis | 3 | 3 | 0.25 | 10 | 8 | 18 | 2.03 | 8.21 | Common along canals. | |||||
| Thryothorus felix | 2 | 7 | 1 | 1 | 11 | 0.91 | 3 | 11 | 8 | 22 | 2.48 | 2.74 | ||
| Thryothorus sinaloa | 1 | 7 | 8 | 0.66 | 2 | 2 | 0.23 | −2.92 | ||||||
| Tyrannus melancholicus | 11 | 19 | 2 | 5 | 37 | 3.05 | 4 | 15 | 10 | 29 | 3.27 | 1.07 | Under sampled with nets. | |
| Oreothlypis luciae | 4 | 1 | 5 | 0.41 | 3 | 21 | 3 | 27 | 3.04 | 7.38 | Now an abundant breeder in mesquite forest. | |||
| Vireo bellii | 2 | 1 | 3 | 0.25 | 1 | 9 | 13 | 23 | 2.59 | 10.48 | Now an abundant breeder in ecotones. | |||
| Volatinia jacarina | 3 | 1 | 4 | 0.33 | 3 | 5 | 8 | 0.90 | 2.74 | Now common in weedy fields. Flies through nets, so under sampled in recent collecting. | ||||
| Totals/Mean AI values | 356 | 0.98 | 380 | 1.43 | 2.97 | |||||||||