Pathways to Science Opportunities database

great searchable database for international opportunities. Sponsored by the Institute for Broadening Participation: Pathways to Science

http://www.pathwaystoscience.org/Undergrads.asp

Opportunities through the International Computational Biology Society

http://www.iscb.org/iscb-careers

Mostly opportunities for PhDs listed here but there often are graduate student fellowships too

Phycological Society of America: Graduate student opportunities

The Phycological Society of America is a professional society devoted to the study of algae and algal-like organisms. Professors who have funding and are looking for graduate research students will often post these positions at

https://www.psaalgae.org (go to the Opportunities page)

Jobs, internships, grad opportunities from Society of Conservation Biology

Includes jobs, internships, graduate assistantships, courses

https://conbio.org/professional-development/

The Society for Conservation Biology (SCB) is an international professional organization dedicated to promoting the scientific study of the phenomena that affect the maintenance, loss, and restoration of biological diversity. The Society's membership comprises a wide range of people interested in the conservation and study of biological diversity: resource managers, educators, government and private conservation workers, and students make up the more than 5,000 members world-wide.  

Opportunities posted at American Society for Plant Biology

https://jobs.plantae.org

The American Society for Plant Biology is a professional society devoted to the science of plants.

International Society of Limnology: Graduate school opportunities

The International Society of Limnology is a professional society devoted to the study of freshwater systems. Professors/researchers who have funding for student research fellowship positions will commonly advertise them at: 

https://limnology.org/jobs/job-announcement/

Jobs related to the field are also posted here, although many of the posting require higher degrees than B.A./B.S.

Opportunities through the Entomological Society of America

http://www.entsoc.org/listjobs

The Entomological Society of America is a professional society geared towards the study of insects. Many of the jobs seemed to be geared more towards advanced degrees, but there are graduate assistantships listed in here as well.

American Phytopathology Society - Jobs, graduate assistantships

The American Phytopathology Society is a professional society devoted to studying plant diseases. This posting board lists regular jobs as well as graduate school opportunities

https://www.apsnet.org/careers/jobcenter/Pages/FindaJob.aspx

Society for Integrative and Comparative Biology - Jobs, Fellowships

This searchable posting board lists jobs and graduate fellowship opportunities. The focus tends to be on evolutionary and ecological programs of research.

http://www.sicb.org/jobs.php3

opportunities in Biology - New Scientist database

A database of jobs and Ph.D. positions in Biology

https://jobs.newscientist.com/jobs/studentships-and-courses/

Job postings with American Soc SE Biologists (ASB)

The American Society of Southeast Biologist (ASB) posts many general Biology jobs. Most require Masters level or higher but occasionally there are jobs appropriate for recent bachelor's degree students and graduate school fellowships.


http://sebiologists.org/jobs.html

Opportunities through the Society of Toxicology

https://www.toxicology.org/careers/

Opportunities from Crop/SoilAgronomy societies

https://www.careerplacement.org

Opportunities through the Society for Marine Mammology

http://marinemammalscience.org/jobs-grants/marine-mammal-science-job-openings/

Opportunities through the Oceanography Society

https://tos.org

Jobs: https://jobs.tos.org

Internships, summer research for undergrads: https://tos.org/undergrad 

Opportunities through the North American Membrane Society

https://membranes.org/membrane-jobs/

Opportunities from the Biophysical Society

https://biophysics-jobs.careerwebsite.com

Opportunities through the American Society of Virology

https://jobs.asv.org

Opportunities through American Society for Photobiology

http://photobiology.org/wp/jobs.php

Opportunities through American Brylogical and Lichenology Society

http://www.abls.org