Progress 10/01/07 to 09/30/08
Outputs
OUTPUTS: Outputs _ 1/25/09 _ I modified an earlier field technique for studying the growth and survival of apical tips and shoots of Rockweed, Ascophyllum nodosum. Small color coded cable ties were used for marking individual apical tips. Large cable ties with numbered tags were fastened around the base of the alga to identify individual shoots. The small cable ties were attached snugly (not tightly) on the shoot (module) below the second vesicle (bladder). These procedures minimized girdling damage which could lead to the loss of apical and sub-apical tips. The seasonal measurement of tips allows growth rate and survival to be estimated and correlated with season, environmental, and biological variables. In addition, individual shoots are periodically returned to the laboratory for chemical analyses and measurement. These basic measurements will provide data for comparative analysis and testing possible long-term changes in growth rates. I have shared these methods
and rationale with colleagues and students, as noted below. I have discussed aspects of the preliminary findings of the field growth studies on A. nodosum with biologists at the Bigelow Laboratories, the Department of Marine Resources, Suffolk University, University of New Brunswick and the University of Maine (UM). I have shared this information with colleagues at UM, the Northeast Algal Society, and the New England Estuarine Research Society. I have spoken with members of the Maine Seaweed Council (a pro-seaweed organization concerned with the growth and sustainable use of A. nodosum and other seaweeds). I regularly respond to letters and phone calls on this and other seaweed resources. I have involved colleagues and students in these studies including: Dr. Brian Beal, a marine ecologist from the University of Maine at Machias (UMM), He has assisted with sampling and tagging in the Jonesport region, and will assist with statistical analyses. He has periodically contributed
undergraduates from UMM for assistance with field studies. Also, I have had assistance with tagging and growth measurements from Dennis Anderson, a UM research associate, several UM undergraduates and my son, an aquatic ecologist from the State of Washington. Lastly an honor, work study student (Shannon Alexa) is gaining valuable research experience assisting with algal measurements, salinity determinations, entering current and 1970's growth data on spreadsheets for comparative analysis. She is also starting an honors project on an aspect of growth. We may present a poster at a regional meeting in Spring 2009. Upon completion of field measurements (July, 2009), data entry and statistical analyses (Fall, 2009), the results will be presented at regional and national conferences and workshops. We will publish two or three papers from this work including: Temporal and spatial variability in the growth of A. nodosum; Influence of elevated temperatures on the phenology, growth and
reproduction of A. nodosum; Climate change and the comparative growth of A. nodosum over three decades. PARTICIPANTS: Dr. Brian Bea l, Univ. of Maine at Machias, assisted with tagging studies and water sampling in the Jonesport area and will assist with statistical analyses. Dennis Anderson, Associate Scientist, Univ. of Maine, assisted with growth tagging studies in the Sheepscot area. Shannon Alexa, an Honors work-study student, assisted with laboratory measurements and data entry. My son and several undergraduates have participated in one or two sampling efforts. TARGET AUDIENCES: Marine resource and conservation managers (Department of Marine Resources: Nature Conservancy, etc.) in Maine, New Brunswick and New England; Marine and climate change ecologists and phycologists; Maine Seaweed Council, Seaweed Harvesters and informed "conservation" public. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
The results obtained in this work have been shared with the department of Maine Marine Resources and the Maine Seaweed Council. These results on the growth and survival of Rockweed will contribute to the managed growth and sustainable use of this important seaweed.
Publications
- No publications reported this period
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Progress 01/01/07 to 09/30/08
Outputs
OUTPUTS: Outputs _ 1/25/09 _ I modified an earlier field technique for studying the growth and survival of apical tips and shoots of Rockweed, Ascophyllum nodosum. Small color coded cable ties were used for marking individual apical tips. Large cable ties with numbered tags were fastened around the base of the alga to identify individual shoots. The small cable ties were attached snugly (not tightly) on the shoot (module) below the second vesicle (bladder). These procedures minimized girdling damage which could lead to the loss of apical and sub-apical tips. The seasonal measurement of tips allows growth rate and survival to be estimated and correlated with season, environmental, and biological variables. In addition, individual shoots are periodically returned to the laboratory for chemical analyses and measurement. These basic measurements will provide data for comparative analysis and testing possible long-term changes in growth rates. I have shared these methods and rationale with colleagues and students, as noted below. I have discussed aspects of the preliminary findings of the field growth studies on A. nodosum with biologists at the Bigelow Laboratories, the Department of Marine Resources, Suffolk University, University of New Brunswick and the University of Maine (UM). I have shared this information with colleagues at UM, the Northeast Algal Society, and the New England Estuarine Research Society. I have spoken with members of the Maine Seaweed Council (a pro-seaweed organization concerned with the growth and sustainable use of A. nodosum and other seaweeds). I regularly respond to letters and phone calls on this and other seaweed resources. I have involved colleagues and students in these studies including: Dr. Brian Beal, a marine ecologist from the University of Maine at Machias (UMM), He has assisted with sampling and tagging in the Jonesport region, and will assist with statistical analyses. He has periodically contributed undergraduates from UMM for assistance with field studies. Also, I have had assistance with tagging and growth measurements from Dennis Anderson, a UM research associate, several UM undergraduates and my son, an aquatic ecologist from the State of Washington. Lastly an honor, work study student (Shannon Alexa) is gaining valuable research experience assisting with algal measurements, salinity determinations, entering current and 1970's growth data on spreadsheets for comparative analysis. She is also starting an honors project on an aspect of growth. We may present a poster at a regional meeting in Spring 2009. Upon completion of field measurements (July, 2009), data entry and statistical analyses (Fall, 2009), the results will be presented at regional and national conferences and workshops. We will publish two or three papers from this work including: Temporal and spatial variability in the growth of A. nodosum; Influence of elevated temperatures on the phenology, growth and reproduction of A. nodosum; Climate change and the comparative growth of A. nodosum over three decades. PARTICIPANTS: Dr. Brian Bea l, Univ. of Maine at Machias, assisted with tagging studies and water sampling in the Jonesport area and will assist with statistical analyses. Dennis Anderson, Associate Scientist, Univ. of Maine, assisted with growth tagging studies in the Sheepscot area. Shannon Alexa, an Honors work-study student, assisted with laboratory measurements and data entry. My son and several undergraduates have participated in one or two sampling efforts. TARGET AUDIENCES: Marine resource and conservation managers (Department of Marine Resources: Nature Conservancy, etc.) in Maine, New Brunswick and New England; Marine and climate change ecologists and phycologists; Maine Seaweed Council, Seaweed Harvesters and informed "conservation" public. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
The results obtained in this work have been shared with the department of Maine Marine Resources and the Maine Seaweed Council. These results on the growth and survival of Rockweed will contribute to the managed growth and sustainable use of this important seaweed.
Publications
- No publications reported this period
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Progress 10/01/06 to 09/30/07
Outputs
OUTPUTS: I have discussed the objectives and preliminary results of the growth studies on Ascophyllum with marine resource managers, graduate students, colleagues (ecologists and phycologists) in Maine, New Brunswick and New England. Also, I have spoken with members of the Maine Seaweed Council (a non-governmental, pro-seaweed organization). I regularly respond to e-mails and phone calls on Ascophyllum, seaweed resources, sustainable harvest techniques, pollution problems and mariculture issues. In addition, I have involved Dr. Brian Beal, a marine ecologist from the University of Maine at Machias, with sampling and research in the Machias area. In the 1970's I developed a tagging technique (monofilament and plastic water-proof tape) for assessing growth of specific apical tips of Ascophyllum. I modified the technique in the current project by using color-coded cable ties for marking the shoots and apical tips. The cable ties are easily attached to the shoots and cause minimum damage
to the alga. I have shared this methodology with colleagues and students, as noted above. Lastly, I have a work study student entering growth data from the 1970's on spreadsheets for comparative analysis.
PARTICIPANTS: Dr. Brian Beal, Univ. of Maine at Machias, assisted with tagging studies and water sampling. Dennis Anderson, Associate Scientist, Univ. of Maine, assisted with tagging studies. Shannon Alexa, Work study student, assisted with laboratory measurements and data entry.
TARGET AUDIENCES: marine resource managers in Maine, New Brunswick and New England, marine and climate change ecologists and phycologists, Maine Seaweed Council and informed "conservation" public.
PROJECT MODIFICATIONS: 1) The number of long-term sites have been reduced from eight to six. This was caused by time and resource considerations.
Impacts
The overall goals of this research are to determine if the annually produced apical tips and the subtending annual growth increments "modules" of rockweed (Ascophyllum nodosum) can be used as an expression of present-day thermal condition and provide an historical index of growth and temperature change over the last two to three decades in the Gulf of Maine. Six field sites were utilized for tagging and long-term growth studies. These sites, three in the southwest region (Montsweag Bay, Sheepscot River, Pemaquid Beach) and three in the northeast region (Great Wass Island, Jonesport, Roque Bluffs) were sampled regularly for temperature, salinity, seawater nutrients (nitrate, dissolved phosphate, total phosphate) and seasonally for growth. In addition, light extinction depth measurements were made with a secchi disk at representative stations at or near the field sites. Originally, I planned to sample four permanent sites in each region, but logistic and resource
considerations limited the number of long-term sites. Additional (random) sites will also be utilized for phenological and growth (regression) analyses. Sampling of rockweed for phenological patterns was begun during the fall of 2006. Preliminary analyses suggest that growth in 2007 extends later into fall than normal (herein during the 1970's and 1980"s). If the extension of growth into mid or late fall is real, then this increase should be reflected in the lengths of the subtending (2007) modules in spring of 2008. The time of initiation of growth of new apical tips in spring, however, appears to be unchanged and similar to the 1970's. Observation of reproductive receptacles indicates that dehiscence of receptacles occurs four to six weeks earlier than normal. This suggests that gamete release is also initiated earlier in spring or that the window of release has been compressed. The net effect appears to be a shorter, narrower period of gamete release, reproductive activity and
recruitment. Growth studies based on tagged shoots and tagged canopy (apical) tips showed considerable variation between sites. Generally, the lengths of canopy tips were similar within plants and within sites, except for Bar Island, which was blocked statistically, because of the apparent differences in habitat and tidal flow. Annual growth rates for the six populations tagged in 2007 ranged from 1.9% (Bar Island) to 2.4% (Ferry). The mean (annual) lengths (mm) of apical tips were: Ferry (145.2), Clough Point (104.6), Black Duck Cove (96.4), Rogue Bluffs (90.3), Pemaquid Beach (69.9), Bar Island (69.5). The higher annual growth patterns appear to reflect both reduced water movement and slightly warmer seawater temperatures. Data on the patterns of growth of subtending modules have not been completed nor analyzed. Data from the 1970's are being entered on spread sheets.
Publications
- No publications reported this period
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