uid=HFR,o=lter,dc=ecoinformatics,dc=org all public read doi:10.6073/pasta/be5e0992584087f37bbef0df42cd8a8c Brooks Mathewson Elizabeth Colburn David Foster https://orcid.org/0000-0003-1171-3762 Researcher 2023 English

Eastern hemlock (Tsuga canadensis), an important late successional tree species, is currently threatened in this region by the hemlock woolly adelgid (Adelges tsugae), a small aphid-like invasive insect from Japan. While many species of birds and mammals have found to be associated with eastern hemlock dominated stands, there have been very few studies examining amphibian relative abundance in this forest type. Eastern redback salamanders (Plethodon cinereus) are important components of the forest ecosystem as they are extremely abundant with a biomass found to be twice that of breeding birds and equal to small mammals in the Hubbard Brook Experimental Forest. In addition, redbacks are positioned in the middle of the food web where they are important predators of soil invertebrates, potentially impacting soil respiration rates, and prey for larger vertebrates such as birds, reptiles, and small mammals. Redbacks have been cited as excellent indicators of forest health due to these characteristics as well as their low annual variation in abundance compared to other forest fauna. The objectives of this study was to 1) establish baseline data on eastern redback salamander relative abundance in eastern hemlock dominated stands and mixed deciduous stands in the Harvard Forest in Petersham, MA using artificial cover objects (ACOs) 2) test for differences in redback relative abundance based on forest type, 3) test for correlations between redback relative abundance and soil pH and forest floor temperature.

This study provides baseline estimates of juvenile eastern red-spotted newt (Notophthalmus viridescens viridescens) or "red eft" minimum density through visual surveys of transects in ten forest stands, five eastern hemlock (Tsuga canadensis) dominated and five mixed deciduous, located in the Prospect Hill, Slab City, Simes, and Tom Swamp tracts of Harvard Forest. The objectives of this study were to 1) acquire baseline minimum red eft density data at Harvard Forest, 2) test for potential differences in minimum density based on forest type, 3) test for correlations between minimum density and soil pH and forest floor temperature, 4) test for seasonal differences in minimum density estimates.

Intensive two minute searches of 1-m2 were conducted to measure eastern redback salamander (Plethodon cinereus) abundance and juvenile eastern red-spotted newt (Notophthalmus viridescens viridescens) or "red eft" abundance at ten stands, five eastern hemlock (Tsuga canadensis) dominated and five mixed deciduous stands, in the Prospect Hill, Slab City, Simes, and Tom Swamp tracts of Harvard Forest in fall 2003 and spring 2004. The objective of this study was to supplement other studies using artificial cover objects (ACOs) to measure eastern redback salamander relative abundance and transect walks to measure minimum density of red efts at Harvard Forest.

Plethodontid salamanders are increasingly being cited as important indicators of forest health as they are major contributors to the overall faunal biomass in a forest. In addition, they are positioned in the middle of the food web where they are important predators of soil invertebrates, potentially impacting soil respiration rates, as well as prey for higher vertebrates such as birds, small mammals, and reptiles. Plethodon species also have lower annual coefficients of variation than other animals due to their small home ranges and terrestrial breeding habits. A relatively new technique used in assessing plethodontid abundance is the installation and monitoring of artificial cover objects (ACOs). Wood ACOs of different sizes have been effectively used as terrestrial salamander monitoring tools. However, there is a concern that the quality of habitat under wooden cover objects may change over time as they weather thus altering their ability to track real changes in salamander abundance. More rot-resistant materials such as asphalt shingles may provide more consistent habitat over time. This study compared the observation rates of the most common plethodontid species in this region, the eastern redback salamander (Plethodon cinereus) under artificial cover objects (ACOs) of the same surface area - 1m x 0.25m - but different materials - 2cm thick rough-cut eastern hemlock boards and asphalt shingles.

abundance hemlock hemlock woolly adelgid salamanders LTER controlled vocabulary populations 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=hf075 Harvard Forest. Coordinates based on WGS84 datum. -72.22 -72.17 +42.54 +42.45 230 340 meter 2003 2004 genus Adelges species tsugae hemlock woolly adelgid genus Ambystoma species maculatum spotted salamander genus Notophthalmus species viridescens eastern red-spotted newt genus Plethodon species cinereus eastern redback salamander genus Tsuga species canadensis eastern hemlock 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

ACO stations were set up at 50m intervals along transects in the Prospect Hill, Slab City, Simes, and Tom Swamp tracts of Harvard Forest. Each ACO station consisted of one 2cm thick rough-cut eastern hemlock board (1m x 0.25m) and one asphalt shingle (1m x 0.25m) located 3m apart and parallel to the transect. Each of the ten stands in this study contained between four and twelve ACO stations. ACOs were monitored between one and six times per season. Temperature measurements were obtained through the installation of one remote temperature sensor (iButton) placed in the center of each transect and set to record temperature every half hour in spring 2004 (4/22/04 - 6/7/04) and every hour in fall 2004 (9/22/04 - 11/12/04). In early winter 2003 five soil samples were taken from random points just below the leaf litter in each transect and left to dry for two weeks and then soil pH was measured in the lab.

Minimum red eft density estimates were obtained by counting the number of red efts encountered within 0.5m of both sides of a transect. Between two and six transects were established in each stand. Transect lengths were between 73m and 107m, with the majority (20 of 31 transects) 90m long. Only red efts entirely within the surveyed area were counted. All searches were conducted by the same observer. The number of surveys per season in each stand varied from one to eight. The highest density value obtained for a stand in a season was used as the minimum density of red efts in that stand. This value was used as opposed to the average, because it is assumed that values lower than the maximum were a result of conditions that were not optimal for red efts to be on the surface of the forest floor. Both seasonal averages and maximums are reported in the data set. Temperature measurements were obtained through the installation of one remote temperature sensor (iButton) placed in the center of each transect and set to record temperature every half hour in spring 2004 (4/22/04 - 6/7/04) and every hour in fall 2004 (9/22/04 - 11/12/04). In early winter 2003 five soil samples were taken from random points just below the leaf litter in each transect and left to dry for two weeks and then soil pH was measured in the lab.

Twenty 1-m2 quadrats were searched in each of the ten stands both fall 2003 and spring 2004. Quadrats were selected randomly along transects established in each stand for a companion study examining red eft density using transect walks. Searches were conducted in the last week of September 2003 and the first week of October 2003. In the spring, intensive searches were conducted on eight separate dates between mid-April 2004 and mid-June 2004. On all sampling days an equal number of quadrats were searched in eastern hemlock and mixed deciduous stands, except at one site in the fall in which different forest types were searched on successive days. I searched for redbacks and red efts on the surface of the forest floor, within the leaf litter, and under natural cover objects such as stones and decaying logs. After each search cover objects were restored to as close to their original position as possible.

ACO stations were set up at 50m intervals along transects established for a separate study of red eft minimum density in the Prospect Hill, Slab City, Simes, and Tom Swamp tracts of Harvard Forest. Each ACO station consisted of one 2cm thick rough-cut eastern hemlock board (1m x 0.25m) and one asphalt shingle (1m x 0.25m) located 3m apart and parallel to the transect. Each of the ten stands in this study contained between four and twelve ACO stations. ACOs were monitored between one and six times per season. Temperature measurements were obtained through the installation of one remote temperature sensor (iButton) placed in the center of each transect and set to record temperature every half hour in spring 2004 (4/22/04 - 6/7/04) and every hour in fall 2004 (9/22/04 - 11/12/04). In early winter 2003 five soil samples were taken from random points just below the leaf litter in each transect and left to dry for two week and then soil pH was measured in the lab.

Harvard Forest

324 North Main Street Petersham MA 01366 USA

(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. hf075-01-salamander.csv eastern redback salamander hf075-01-salamander.csv 13318 b300f08802f2d1f6ef980e75a6185731 1 \r\n column , https://harvardforest.fas.harvard.edu/data/p07/hf075/hf075-01-salamander.csv aco artificial cover object number artificial cover object number asn ACO station number ACO station number aco.name original name given to ACO. First two letters are for Simes. Second two letters indicate forest type (TS = hemlock, HW = hardwood or mixed deciduous). First number indicates replicate number of forest type. Following letter indicates which transect ACO is perpendicular to (S = South, N = North, E = East, W = West). Next letter indicates whether ACO is board (B) or shingle (S). Next number indicates position along transect (2 = 20 meters from origin, 7 = 70 meters from origin). original name given to ACO tract Harvard Forest tract in which ACO is located Harvard Forest tract in which ACO is located forest.type forest type forest type aco.type ACO type ACO type lat latitude of ACO latitude of ACO NA missing value long longitude of ACO longitude of ACO NA missing value datum datum for latitude and longitude coordinates datum fa03.n number of times ACO was monitored in fall 2003 number 1 natural NA missing value fa03.avg average number of redbacks found during ACO searches in fall 2003 number 0.01 real NA missing value sp04.n number of times ACO was monitored in spring 2004 number 1 natural NA missing value sp04.avg average number of redbacks found during ACO searches in spring 2004 number 0.01 real NA missing value su04.n number of times ACO was monitored in summer 2004 number 1 natural NA missing value su04.avg average number of redbacks found during ACO searches in summer 2004 number 0.01 real NA missing value fa04.n number of times ACO was monitored in fall 2004 number 1 natural NA missing value fa04.avg average number of redbacks found during ACO searches in fall 2004 number 0.01 real NA missing value 124 hf075-02-newt.csv eastern red-spotted newt hf075-02-newt.csv 6235 7aba57e8c8eb0a4478000ec91fd39fc7 1 \r\n column , https://harvardforest.fas.harvard.edu/data/p07/hf075/hf075-02-newt.csv id identification number identification number replicate replicate number replicate number subsample subsample number subsample number transect transect name transect name forest.type forest type MD mixed deciduous TS eastern hemlock dominated tract Harvard Forest tract. Simes 1 = plots 1-3 and plot 8 in HWA study at Simes Tract. Simes 2 = plots 4-6 and plot 7 in HWA study at Simes Tract. Harvard Forest tract lat latitude of origin of transect latitude of origin of transect NA missing value long longitude of origin of transect longitude of origin of transect NA missing value datum datum for latitude and longitude coordinates datum for latitude and longitude coordinates orientation orientation of transect (degrees) number 1 natural NA missing value length length of transect meter 1 natural NA missing value su03.n number of times transects were walked in summer 2003 number 1 whole NA missing value su03.max.density maximum red eft density found summer 2003 transect walks (individuals/m2) number 0.01 real NA missing value su03.avg.density average red eft density found during summer 2003 transect walks (individuals/m2) number 0.01 real NA missing value fa03.n number of times transects were walked in fall 2003 number 1 natural NA missing value fa03.max.density maximum red eft density found fall 2003 transect walks (individuals/m2) number 0.01 real NA missing value fa03.avg.density average red eft density found during fall 2003 transect walks (individuals/m2) number 0.01 real NA missing value sp04.n number of times transects were walked in spring 2004 number 1 natural NA missing value sp04.max.density maximum red eft density found spring 2004 transect walks (individuals/m2) number 0.01 real NA missing value sp04.avg.density average red eft density found during spring 2004 transect walks (individuals/m2) number 0.01 real NA missing value su04.n number of times transects were walked in summer 2004 number 1 natural NA missing value su04.max.density maximum red eft density found summer 2004 transect walks (individuals/m2) number 0.01 real NA missing value su04.avg.density average red eft density found during summer 2004 transect walks (individuals/m2) number 0.01 real NA missing value fa04.n number of times transects were walked in fall 2004 number 1 natural NA missing value fa04.max.density maximum red eft density found fall 2004 transect walks (individuals/m2) number 0.01 real NA missing value fa04.avg.density average red eft density found during fall 2004 transect walks (individuals/m2) number 0.01 real NA missing value ph measurement of pH directly below leaf litter taken from five samples along each transect number 0.01 real NA missing value ibutton.lat latitude of location of iButton (remote temperature sensor) latitude of location of iButton (remote temperature sensor) ibutton.long longitude of location of iButton (remote temperature sensor) longitude of location of iButton (remote temperature sensor) ibutton.datum datum for iButton latitude and longitude coordinates datum for iButton latitude and longitude coordinates avg.temp.spring average daily temperature (4/22/04 - 6/03/04) measured by one iButton located in the middle of the transect on the surface of the forest floor celsius 0.1 real NA missing value avg.temp.sd.spring standard deviation of daily temperatures (4/22/04 - 6/03/04) measured by one iButton located in the middle of the transect on the surface of the forest floor celsius 0.1 real NA missing value avg.daily.max.spring average daily maximum temperature (4/22/04 - 6/03/04) measured by one iButton located in the middle of the transect on the surface of the forest floor celsius 0.1 real NA missing value avg.daily.min.spring average daily minimum temperature (4/22/04 - 6/03/04) measured by one iButton located in the middle of the transect on the surface of the forest floor celsius 0.1 real NA missing value avg.temp.fall average daily temperature (9/22/04 - 11/13/04) measured by one iButton located in the middle of the transect on the surface of the forest floor celsius 0.1 real NA missing value avg.temp.sd.fall standard deviation of daily temperatures (9/22/04 - 11/13/04) measured by one iButton located in the middle of the transect on the surface of the forest floor celsius 0.1 real NA missing value avg.daily.max.fall average daily maximum temperature (9/22/04 - 11/13/04) measured by one iButton located in the middle of the transect on the surface of the forest floor celsius 0.1 real NA missing value avg.daily.min.fall average daily minimum temperature (9/22/04 – 11/13/04) measured by one iButton located in the middle of the transect on the surface of the forest floor celsius 0.1 real NA missing value 31 hf075-03-searches.csv time-constrained searches hf075-03-searches.csv 1839 03ef78050e5fc536a5e8198526d642f9 1 \r\n column , https://harvardforest.fas.harvard.edu/data/p07/hf075/hf075-03-searches.csv transect name of transect along which quadrat was positioned name of transect along which quadrat was positioned tract Harvard Forest tract in which quadrat was located PH Prospect Hill TS Tom Swamp SC Slab City SI1 Simes tract (plots 1-3 and plot 8 in HWA experiment) SI2 Simes tract (plots 4-6 and plot 7 in HWA experiment) forest.type forest type of stand in which quadrat was located MD mixed deciduous TS eastern hemlock dominated lat latitude of the origin of transect in which quadrat was located latitude of the origin of transect in which quadrat was located NA missing value long longitude of the origin of transect in which quadrat is located latitude of the origin of transect in which quadrat was located NA missing value datum datum for latitude and longitude coordinates datum for latitude and longitude coordinates orientation orientation of transect along which quadrat was located orientation of transect along which quadrat was located fa03.date date on which quadrats along transect were sampled YYYY-MM-DD 1 day NA missing value sp04.date date on which quadrats along transect were sampled YYYY-MM-DD 1 day NA missing value fa03.pc.ab redback abundance in fall 2003 (individuals/m2) number 0.1 real NA missing value fa03.nv.ab red eft abundance in fall 2003 (individuals/m2) number 0.1 real NA missing value sp04.pc.ab redback abundance in spring 2004 (individuals/m2) number 0.1 real NA missing value fa04.nv.ab red eft abundance in spring 2004 (individuals/m2) number 0.1 real NA missing value 21 community short-term measurement https://harvardforest.fas.harvard.edu/exist/apps/datasets/showData.html?id=hf038