Herbarium specimens are dried and pressed plants mounted on archival paper;
By Layla Aerne Hains
For many years, amateur naturalists have made observations on the commonalities they see in nature: documenting the plants they come across on a hike, the daily weather conditions or birds that are passing through on annual migrations. The notes and observations of amateur naturalists are turning out to be a useful tool when trying to reconstruct the living landscape in a particular area. A famous example of an amateur naturalist is Henry David Thoreau who lived at Walden Pond for several years and wrote about the natural environment near his cabin. As a result of Thoreau’s influence, Walden Pond is considered the birthplace of the conservation movement. Amateur naturalists have paved the way for creating research-based projects that use citizen scientists to collect data in their local environments.
The San Diego Natural History Museum historically has relied on volunteers and citizen scientists to help move our scientific knowledge forward. Currently, the Botany Department uses Parabotanists to document the flora from all corners of San Diego County. Parabotanists are citizens of the community (retirees, students, professionals in just about any field) who are working toward the common goal of learning more about the local flora, while helping the Museum by collecting plants for our herbarium.
Herbarium specimens, which consist of dried and pressed plants mounted on acid-free paper, can be used as a tool for climate-change research. Recently published scientific papers describe the importance of museum specimens as a source of information documenting biological response to climate change, because the associated specimen data include dates, locations, and reproductive status (e.g., whether the plant was in flower or had fruit on it). This enables scientists to examine changes in timing of plant reproduction or changes in geographic range or distribution.
Flowering plants provide convincing evidence of a response to global warming. Certain plants are now documented as flowering earlier than in the past because of warmer growing conditions. There is a concern that the synchrony between the timing of plant flowering and the activity of pollinators (or animals that eat the plants and disperse their fruits) may become disrupted.
Many herbaria have collections going back 100 years or more and the problem that arises with historic collections is that the data are not readily available to use in scientific studies. A collection that is not data-based can be compared to a library full of books that are not catalogued; all the information is there but cannot be easily searched or used.
In 2005, the SD Herbarium received a grant from the Institute of Museum and Library Services to create a database of the entire San Diego County collection, which includes specimens collected as early as 1874. As a result, all the information captured on the specimen labels is now in a searchable format.
In addition to databasing the entire San Diego County collection, we received funding to georeference the collection as well. “Georeferencing” refers to assigning a latitude and longitude to a specimen based upon the written locality information. This gives us the ability to map all the specimens in the county for which we have a collection. A collection that is data-based and georeferenced lends itself to innumerable studies including those based on statistical analysis.
We gain a historical perspective from our existing specimens, but now need current data to provide a baseline against which future changes can be analyzed. This leads to the use of citizen scientists to collect valuable data that could otherwise not be obtained by the limited number of scientists in the local community. The San Diego Plant Atlas currently has a pool of over 500 volunteers.
The Plant Atlas project kicked off in 2003 and in the last five years, over 37,000 plants have been collected by the Parabotanists in San Diego County. The volunteers have collected over 200 new taxa that had never been documented in the county before. More recently, the Botany Department is in the beginning stages of a new project that relies on citizen scientists to make observations of the different stages of growth and reproduction (phenology) of flowering plants. These observations will provide that critical baseline needed for future research and will feed into a nationwide project (Project Budburst, www.budburst.org). The local and national aspects of the project will help our understanding of how plants are reacting to a changing climate.
Our understanding of the local flora continues to grow, but there is still so much out there to be discovered. The data that we have collected in the past and what we are currently collecting will only help to broaden our understanding of the intricacies in nature and how those relationships are changing as a response to climate change. Involving the community in the scientific process brings global issues to a local level and gives everyone the sense that these things really are occurring in our own backyards.
For more details about climate change and the Botany Department’s research in this area, see www.sdnhm.org/climatechange.
Beach Sand-Verbena (Abronia umbellata var. umbellata) can seen along the coast in southern California.
SAN DIEGO NATURAL HISTORY: FIELD NOTES, June 2009