March 1 – May 15, 2025
Another Personal Bioblitz is over, our 12th year of organizing this free event to see as many species as we can, together, around the world during 2.5 months. We again had strong engagement by nature enthusiasts around the world to explore and learn about the vast biodiversity in our everyday life, within our homes or nearby, or sometimes during local or longer travel. Again the result is over 50 000 observations and over 100 participants, and we nearly broke the 10 000 species barrier. In this summary we highlight who uploaded the most observation (incomparable Sara Rall in the lead, of course), saw the most species (Annika Lindqvist), and we also highlight the top contributions from Rutgers students. Congratulations to everyone who was part of the Personal Bioblitz 2025, to the winners, and thank you for your contributions to new scientific data and knowledge about biodiversity worldwide. And yes, American Robin (a bird) and several common weeds in New Jersey win the top seen species (again).
The final result for Personal Bioblitz 2025:
55848 observations
8894 species seen
9997 scientific taxa seen [includes observations identified only to genus or to subspecies, etc.]
110 participants [147 members joined the project, but not everyone reported something]
3629 people helped to identify observations uploaded by participants
[Note, these numbers are based on observations seen and uploaded within the set time frames and are verifiable with precise date and locality; iNaturalist data was analyzed on June 30, 2025]
Project website on iNaturalist Project website at Rutgers University
Most observations seen by an observer, 2025
- srall (Sara Rall) – 8471 observations [Again! Sara has been number 1 several years now]
- sedgequeen (Barbara L. Wilson) – 7667 observations [number 2 last year, long-term participant]
- sadawolk (Sandy Wolkenberg) – 3865 observations [number 3 last year, long-term participant]
- annikaml (Annika Lindqvist) – 2883 observations [number 5 last year, long-term participant]
- geosesarma (Austin Mandala) – 2648 observations [Rutgers undergraduate, new participant this year, congratulations!]
Most species seen by an observer, 2025
(this includes all taxa, regardless of rank, to include total biodiversity seen by an observer)
- annikaml (Annika Lindqvist) – 1484 species (1645 taxa)
- sedgequeen (Barbara L. Wilson) – 1135 species (1284 taxa)
- geosesarma (Austin Mandala) – 1031 species (1290 taxa)
- srall (Sara Rall) – 958 species (1037 taxa)
- er1kksen (Erik Danielsen) – 883 species (980 taxa)
Rutgers undergraduate students, most species and observations, 2025
- geosesarma (Austin Mandala) - 2648 observations, 1031 species
- willphill3 (William Phillips) – 432 observations, 134 species
- charonbrown (Sharon Brown) – 184 observations, 99 species
- magnify (Maggie Mannon) – 171 observations, 84 species
- silphidae_seeker (Tyto Jenkins) – 144 observations, 38 species
(known students or self-identified on iNaturalist)
Rutgers graduate students, most species and observations, 2025
- yayabenzvi (Yahel Ben-Zvi) – 956 observations, 345 species
- jwgreenwood (Joanna Greenwood) – 298 observations, 233 species
- mmccarthy98 (Max McCarthy) – 368 observations, 228 species
- kendall_eldredge (Kendall Eldredge) – 25 observations, 24 species
- meganryank (Megan King) – 16 observations, 10 species
(known students or self-identified on iNaturalist)
Most observed species, 2025
- American Robin (Turdus migratorius) – 250 observations [same no. 1 as in 2024]
- Garlic Mustard (Alliaria petiolata) – 232 observations [this was no. 2 in 2024]
- Dandelion (Taraxacum officinale) – 231 observations [new, not in top 5 in 2024]
- Multiflora rose (Rosa multiflora) – 225 observations [new, not in top 5 in 2024]
- Mugwort (Artemisia vulgaris) – 217 observations [new, not in top 5 in 2024]
Plants vs. Animals, 2025
- Plants – 4182 species (41% of all species observed)
- Animals – 4817 species (48% of all species observed)
More and more fungi and lichens are observed; see table of only Fungi and Lichen data:
| Personal Bioblitz Year | Observations | Species |
|---|---|---|
| 2025 | 3,478 | 663 |
| 2024 | 3,488 | 603 |
| 2023 | 4,361 | 693 |
| 2022 | 4,608 | 570 |
| 2021 | 4,518 | 444 |
| 2020 | 1,742 | 354 |
| 2019 | 1,369 | 266 |
| 2018 | 1,406 | 286 |
| 2017 | 1,007 | 219 |
Increased participation from Puerto Rico over the years; see table of only Puerto Rican data:
| Personal Bioblitz year | Observations | Species |
|---|---|---|
| 2025 | 1019 | 439 |
| 2024 | 134 | 109 |
| 2023 | 562 | 370 |
| 2022 | 1029 | 598 |
| 2021 | 474 | 307 |
| 2020 | 135 | 96 |
| 2019 | 39 | 34 |
| 2018 | 133 | 101 |
| 2017 | 4 | 4 |
New Jersey Participation and Results by Year (last 7 years):
2025: 13337 observations; 2208 species; 56 observers
2024: 19208 observations; 2974 species; 67 observers
2023: 18995 observations; 2876 species; 87 observers
2022: 18422 observations; 1973 species; 59 observers
2021: 21462 observations; 2034 species; 62 observers
2020: 8532 observations; 1366 species; 29 observers
2019: 6147 observations; 1024 species; 27 observers
The Personal Bioblitz 2025 leadership team consisted of Lena Struwe, Ivelisse Irizarry, Eva Hedström, Herve’ Barrier, Paul Foster, Jason R Grant, Annika Lindqvist, Jeff Mollenhauer, Sara Rall, Bonnie Semmling, and Blair Young.
Updates and corrections to this list can be sent to Lena Struwe, email: lena.struwe@rutgers.edu.
Thank you!
Lena Struwe, Director of Chrysler Herbarium, Rutgers University
7 July 2025