An award has been made to the University of Hawaii under the direction of Dr. Alison Sherwood to conduct a biological inventory of the freshwater algae of the Hawaiian Islands. Dr. Patrick Kociolek of the University of Colorado at Boulder, and Dr. Jeffrey Johansen of John Carroll University are collaborators on the research. This project will produce the first comprehensive, well-illustrated freshwater algal flora of a tropical region for anywhere in the world. The principal freshwater habitats of the main Hawaiian Islands will be surveyed and collections will be identified using morphological and molecular analyses. The objectives are to 1) establish long-term archived collections of Hawaiian freshwater algae morphological and genetic studies, 2) make all data available through a project database and website, and 3) describe newly discovered freshwater algal taxa from the Hawaiian Islands. This project blends traditional taxonomy with bioinformatic analysis and data display. The survey brings together a top-tier team of algal taxonomists, all of whom have previous experience with the Hawaiian algal flora, to collect, document and describe the freshwater algae of the Hawaiian Islands. Work will be coordinated through the University of Hawaii and will bring together researchers from four different institutions and enhance partnerships with multiple agencies.
Five graduate students, five undergraduate students and a postdoctoral fellow will be trained in algal surveying and culturing techniques, morphological identification of freshwater algae and molecular methods. Pacific Islander undergraduate students will be hosted through research internships each of three summers through the University of Hawaii?s Undergraduate Mentoring in Environmental Biology program. A year-round undergraduate research internship for a Native Hawaiian student will be hosted at the University of Hawaii. A family program of stream exploration through the Hawaii Nature Center will be offered each summer, aimed at middle school students. Surveys in taro fields will foster communication between the researchers and farmers from the Native Hawaiian community. In addition, the results of the proposed surveys will be made available to the scientific community and beyond through the establishment of: 1) the online Hawaiian Freshwater Algal Database, and 2) a website providing summary data for species.
Over a thousand samples were collected from freshwater and subaerial habitats in the accessible main islands of the Hawaiian Archipelago. From these samples, over 350 cyanobacterial isolates were made, and these are maintained in a culture collection at John Carroll University and will continue to be a resource for future research. During the course of the project we discovered three new genera of cyanobacteria, 22 new species of cyanobacteria, and five new diatom species. We anticipate more discoveries in the existing preserved samples and isolates as we continue our discoveries in the existing preserved samples and isolates as we continue our studies with the resources obtained during the grant period. We show just a few examples of some of these charismatic microalgae as part of this report. Six scientific manuscripts have been published or accepted for publication, and two additional manuscripts are near submission. We will likely publish three more papers in the near future based on data presently in hand. The project has had a significant impact on human resources by providing meaningful research opportunity and training for seven undergraduate students (including 5 female students, three of which were from under-represented minorities) and two female graduate students. All but one of these students has either gone on to further graduate training or scientific research in the private sector, an indication that the research was meaningful if not transformative in these student's lives. In addition, three students traveled from foreign countries (Czech Republic, Russian Federation) with external funding obtained in competitive awards from their countries of origin in order to receive training in the Johansen laboratory and work with the samples and isolates collected as part of the project. A total of 12 presentations were given at regional, national, and international meetings, most by student researchers, all with student coauthors. This was also valuable training for the students involved. This study has demonstrated some unexpected findings. First, we have found a very high proportion of the algal taxa (both cyanobacteria and diatoms) are species unique to the Hawaiian Archipelago, i.e. they are species new to science, and a fair number of very divergent lineages (genera) are also found only in the islands. This challenges the hypothesis put forward by Lourens Baas Becking in 1936 that in regards to microbial taxa "everything is everywhere, but the environment selects." From our work it is clear that many lineages of freshwater algae are found only in the Hawaiian Islands, and furthermore, many of the most common algae world-wide are conspicuously absent from the islands. Many researchers have challenged this dictum before the present study, but this work strongly supports the idea that barriers to dispersal do exist for microbial taxa, and consequently rare colonization events followed by adaptive radiation occur in microbial species just as this process of evolution occurs in more macroscopic species. Second the algal flora is actually fairly impoverished, i.e. we would expect more species than we actually find if we were studying a similar set of habitats on a continent. This is further evidence of the existence of dispersal barriers. Third, it appears that some of the freshwater taxa in Hawaii have close phylogenetic relationships with marine taxa, suggesting that some of the unique taxa have likely invaded freshwater habitats from the ocean. We have done our taxonomic study using what is known as the polyphasic approach. This entails using a variety of character sets to characteriza and identify isolates, including microscopy, 16S rRNA gene sequence data, analysis of secondary chemical structure of the 16S-23S ITS region, ecological preference, and biogeography. While we are not the first by any means to suggest this modern approach, we have been some of the most active practitioners of this method in cyanobacterial taxonomy. We feel our work has stimulated others in diverse labs around the world to adopt these methods, and consequently our work has had an impact on microbial biodiversity studies and description of novel taxa.
