Stream Macroinvertebrates in Hemlock and Deciduous Watersheds at Harvard Forest 2005-2007

doi:10.6073/pasta/c5e6555def9baf3e53180395e9e15099 Stream Macroinvertebrates in Hemlock and Deciduous Watersheds at Harvard Forest 2005-2007 James Willacker https://orcid.org/0000-0002-6286-5224 William Sobczak Elizabeth Colburn 2023 English

Tsuga canadensis (Eastern Hemlock) is a common forest species that is declining throughout its range in the eastern United States because of the invasion of an non-native forest pest, Adelges tsugae (Hemlock Woolly Adelgid). This pest kills infected trees, and over time, infected stands are replaced by deciduous forests. The conversion of forests from Hemlock to deciduous species is predicted to impact the hydrology, chemistry, and biology of associated headwater streams. In this study, we examined the macroinvertebrate communities of two adjacent headwater streams with differing Hemlock influence in central Massachusetts. Abundance, taxa richness, diversity, and unique taxa were generally greater in the deciduous stream. Differences in the distribution of functional feeding groups were observed: the Hemlock stream had a greater percentage of collector-gatherers while the deciduous stream had a greater percentage of shredders and predators. These findings suggest that macroinvertebrate communities in streams draining Hemlock and deciduous watersheds may differ in structure and function, and that anticipated Hemlock mortality may impact the region’s stream ecology.

hemlock hemlock woolly adelgid macroinvertebrates stream ecology LTER controlled vocabulary disturbance LTER core area Harvard Forest HFR LTER USA HFR default

This dataset is released to the public under Creative Commons CC0 1.0 (No Rights Reserved). Please keep the dataset creators informed of any plans to use the dataset. Consultation with the original investigators is strongly encouraged. Publications and data products that make use of the dataset should include proper acknowledgement.

Creative Commons Zero v1.0 Universal https://spdx.org/licenses/CC0-1.0.html CC0-1.0 https://harvardforest.fas.harvard.edu/exist/apps/datasets/showData.html?id=hf121 Prospect Hill Tract (Harvard Forest). Coordinates based on WGS84 datum. -72.20 -72.17 +42.55 +42.53 280 420 meter 2005 2007 genus Tsuga species canadensis eastern hemlock genus Adelges species tsugae hemlock woolly adelgid complete Information Manager Harvard Forest

324 North Main Street Petersham MA 01366 USA

(978) 724-3302 hf-im@lists.fas.harvard.edu Harvard Forest

324 North Main Street Petersham MA 01366 USA

(978) 724-3302 (978) 724-3595 https://harvardforest.fas.harvard.edu

Field collection Invertebrate samples were taken from four randomly chosen locations in each stream during a two-week period in late July and early August of 2005. At each location, one sample was taken from the nearest riffle area and one from the nearest depositional area; thus, eight samples were taken from each stream. Moss was sampled when present on the substratum. Peak emergence of insects usually occurs in early to late spring; hence, it is likely that our sampling regime underestimated the abundance, richness, and diversity of the streams’ macroinvertebrate communities. Samples were taken by thoroughly disturbing the substrate within a 0.25-m2 quadrat for a 30-second period and collecting all dislodged material in standard D-frame kick nets (250-μm mesh) placed downstream. Samples were live-picked, with care being taken to collect all sizes of specimens.

Laboratory methods and analysis In the laboratory, invertebrates were sorted and identified to the genus level (with the exception of Chironomidae, which were identified to the subfamily/tribe level) using dissecting and compound microscopes. Taxa were then segregated among the grazer, shredder, collector-gatherer, collector-filterer, and predator functional feeding groups based on the ecological information known for each taxon (Merritt and Cummins 1996, Stewart et al. 1993, Wiggins 2000). In addition, taxa unique to each stream were identified. We calculated mean abundance (number of specimens/m2), richness (number of taxa/sample), and Shannon’s diversity index of macroinvertebrates in each stream and compared them using a Student’s t-test. In addition, the composition of the two streams was compared at the order level and among functional feeding groups.

Harvard Forest Long-Term Ecological Research Harvard Forest

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(978) 724-3302 (978) 724-3595 https://harvardforest.fas.harvard.edu https://ror.org/059cpzx98 pointOfContact The Harvard Forest Long-Term Ecological Research (LTER) program examines ecological dynamics in the New England region resulting from natural disturbances, environmental change, and human impacts. National Science Foundation LTER grants: DEB-8811764, DEB-9411975, DEB-0080592, DEB-0620443, DEB-1237491, DEB-1832210. hf121-01-abundance.csv macroinvertebrate abundance hf121-01-abundance.csv 2009 5ba02dbe92185d086a25dce7f4bdf5f5 1 \r\n column , https://harvardforest.fas.harvard.edu/data/p12/hf121/hf121-01-abundance.csv species species name species name order order name order name group functional feeding group functional feeding group hemlock mean abundance for hemlock stream number 0.1 real NA missing value deciduous mean abundance for deciduous stream number 0.1 real NA missing value 48