- H.T. Harvey & Associates
- H.T. Harvey & Associates Ecological Consultants [USA]
- H.T. Harvey & Associates [CA, USA)
- H.T. Harvey and Associates Ecological Consultants [USA]
- HABITER - EA 2076
- HESAM Université - Communauté d'universités et d'établissements Hautes écoles Sorbonne Arts et métiers université
- Halfmoon Biosciences
- Halieutique Manche Mer du Nord
- Halpin Wildlife Research
- Hatfield Marine Science Center [Newport, USA]
- Hawai'i Institute of Marine Biology
- Hawk Mountain Sanctuary [Pennsylvania]
- HawkWatch International [USA]
- Hebei University
- Hellenic Centre for Marine Research
- Helmholtz Centre for Ocean Research [Kiel]
- Helmholtz Zentrum für Umweltforschung = Helmholtz Centre for Environmental Research
- Helsingin yliopisto = Helsingfors universitet = University of Helsinki
- Helsinki Institute of Life Science
- Herbier de Nouvelle-Calédonie
- Herdwangen-Schönach
- High North Research Centre for Climate and the Environment
- High North Research Centre on Climate and the Environment
- Hokkaido University [Sapporo, Japan]
- Holar University College
- Hong Kong University of Science and Technology
- Hopkins Marine Station [Stanford]
- Horticultural Research Group
- Hospices Civils de Lyon
- Hudelson Consulting [Canada]
- Humboldt State University
- Hungarian Natural History Museum (Magyar Természettudományi Múzeum)
- Háskóli Íslands [Reykjavik, Iceland]
- Hôpital Bretonneau