Research
DatabasesThis database includes information on the abundance of birds and the composition of the vegetation in 40 tidal marshes in Connecticut. The abbreviations for the variables listed in this table are explained below. These data are analyzed in the following paper in Wetlands:
Benoit, L. K. and R. A. Askins. In press. Impact of the spread of Phragmites on the distribution of birds in Connecticut tidal marshes. Wetlands 19 (1).
Abstract: Dense monocultures of Phragmites australis (common reed) have been rapidly expanding in Connecticut's tidal wetlands at the expense of cordgrass (SpartinaTypha spp). Bird and vegetation surveys in 40 salt and brackish marshes showed that there were significantly fewer species of birds and state-listed species in Phragmites-dominated wetlands than in short-grass marshes. Seaside Sparrow, Salt-marsh Sharp-tailed Sparrow, and Willet, three marsh specialists adapted to nesting in short graminoids, had low frequencies in plots dominated by Phragmites. Marsh Wren and Swamp Sparrow, however, are marsh specialists that prefer tall, reedy vegetation, and both species had significantly greater densities at sites with more Phragmites or cattail. Although the bird communities of cattail sites and Phragmites sites were similar, the abundance of Virginia Rails was positively correlated with percent cover of cattail but not Phragmites. The extent of pools was positively related to bird species richness in short-grass meadows but not in Phragmites plots. In Phragmites-dominated wetlands, the height and density of reed stands may inhibit bird use of any pools that are present. Muskrats create pools that may enhance bird species richness, but populations of this mammal have dwindled during the same time period that Phragmites increased in Connecticut's marshes. Although a few species may benefit from reed invasion, it has a negative impact on some marsh bird species that have already declined. These findings support the continued need for marsh restoration and the control of common reed.
E-mail address for Robert Askins (Connecticut
College): raask@conncoll.edu
Abbreviations used in Table 1.
| Birds | ||
| Abbrev. | Common Name | Scientific name |
| CM | Double-crested Cormorant | Phalacrocorax uritus |
| GH | Green Heron | Butorides striatus |
| GE | Great Egret | Casmerodius albus |
| SE | Snowy Egret | Egretta thula |
| BN | Black-crowned Night-heron | Nycticorax nycticorax |
| LB | Least Bittern | Ixobrychus exilis |
| GI | Glossy Ibis | Plegadis falcinellus |
| CG | Canada Goose | Branta canadensis |
| MD | Mallard | Anas platyrhynchos |
| BD | Black Duck | Anas rubripes |
| OS | Osprey | Pandion haliaetus |
| CR | Clapper Rail | Rallus longirostris |
| KR | King Rail | Rallus elegans |
| VR | Virginia Rail | Rallus limicola |
| WL | Willet | Catoptrophorus semipalmatus |
| SP | Spotted Sandpiper | Actitis macularia |
| Semi | Semipalmated Sandpiper | Calidris pusilla |
| LS | Least Sandpiper | Calidris minutilla |
| CT | Common Tern | Sterna hirundo |
| LT | Least Tern | Sterna albifrons |
| CS | Chimney Swift | Chaetura pelagica |
| EK | Eastern Kingbird | Tyrannus tyrannus |
| WF | Willow Flycatcher | Empidonax traillii |
| TS | Tree Swallow | Tachycineta bicolor |
| BK | Bank Swallow | Riparia riparia |
| RS | Rough-winged Swallow | Stelgidopteryx ruficollis |
| BS | Barn Swallow | Hirundo rustica |
| PM | Purple Martin | Progne subis |
| MW | Marsh Wren | Cistothorus palustris |
| YT | Common Yellowthroat | Geothylpis trichas |
| RW | Red-winged Blackbird | Agelaius phoeniceus |
| ST | Saltmarsh Sharp-tailed Sparrow | Ammodramus caudacutus |
| SS | Seaside Sparrow | Ammodramus maritima |
| SW | Swamp Sparrow | Melospiza georgiana |
| GF | American Goldfinch | Carduelis tristis |
| Plants | ||
| Abbrev. | Scientific name | |
| SAT | Spartina alterniflora (tall) | |
| SAS | Spartina alterniflora (short) | |
| SP | Spartina patens | |
| JG | Juncus gerardi | |
| DS | Distichlis spicata | |
| PA | Phragmites australis | |
| TY | Typha spp. | |
| FRB | forbs | |
| IF | Iva frutescens | |
| PV | Panicum virgatum | |
| SR | Scirpus robustus | |
| Eleo | Eleocharis spp. | |
| ScA | Scirpus americanus | |
| S cyn | Spartina cynosuroides | |
| algae | algae | |
| Sc spp. | Scirpus spp. | |
| Ags | Agrostis stolonifera var. palustris | |
| Spec | Spartina pectinata | |
| ZA | Zizania aquatica | |
| Other | ||
| Abbrev. | ||
| flot | flotsam | |
| flat | mud flat | |
| Crk | creek | |
| Pool | Pool | |
| Ditch | mosquito ditch | |
| Riv | river |
Research
Databases