Nine times on each count morning, at 8:00, 8:30 and every half hour through 12:00, the site leaders at every Sanctuary Ocean Count site scan the water for exactly 15 minutes and tally each humpback whale they see at the surface. Those nine tallies, split into adults and calves, become the published results. The volunteers around them record what the whales are doing.
NOAA’s Hawaiian Islands Humpback Whale National Marine Sanctuary runs the count on the last Saturday of January, February and March, from shore sites on Oʻahu, Kauaʻi, Molokaʻi and Hawaiʻi Island. The 2027 dates are January 30, February 27 and March 27. Everything here comes from the sanctuary’s data sheets and site leader guide. We are an independent site and not part of the program.
The 15-minute census scans
The census is the site leaders’ job, and they fill in one Census Sheet per site per count. At the start time each leader scans slowly from left to right, giving every part of the water the same amount of time. Each whale seen gets a bar in the Adults or Calves column. A whale already counted in that 15-minute period isn’t counted again, and only whales at the surface during those 15 minutes go on the sheet.
The last scan starts at 12:00 and closes at 12:15, so the sanctuary gives the count’s hours as 8:00 am to 12:15 pm while the registration page asks volunteers to commit to 8 am to noon. Between scans the leaders tally their bars and circle the total, so a data analyst cannot misread “II” as eleven.
How long before the first whale? Across the 2007 to 2026 site tables, three out of four Hawaiʻi Island site-mornings in January and February had logged a whale within the first three scans (8:00 to 9:15), and 87% had by the end of the noon scan. Oʻahu and Kauaʻi sites were quicker: 89% and 95% within the first three scans. In late March the curves drop everywhere, and on Hawaiʻi Island only half of the site-mornings had a whale by 9:15.
| Island, months | site-mornings | by 15 min | by 30 min | by 45 min | by 60 min | by 75 min | by 90 min | by 105 min | by 120 min | by 135 min |
|---|---|---|---|---|---|---|---|---|---|---|
| Hawaiʻi, Jan–Feb | 583 | 60% | 69% | 75% | 79% | 81% | 84% | 85% | 86% | 87% |
| Hawaiʻi, Mar | 275 | 33% | 44% | 49% | 53% | 56% | 59% | 60% | 60% | 60% |
| Oʻahu, Jan–Feb | 754 | 71% | 84% | 89% | 91% | 93% | 94% | 95% | 95% | 96% |
| Oʻahu, Mar | 359 | 56% | 71% | 77% | 79% | 82% | 84% | 86% | 87% | 87% |
| Kauaʻi, Jan–Feb | 482 | 84% | 94% | 95% | 96% | 97% | 99% | 99% | 99% | 99% |
| Kauaʻi, Mar | 226 | 67% | 80% | 83% | 86% | 88% | 90% | 91% | 92% | 93% |
The census sheet also has rows for spinner dolphins and other species, and the site leader guide adds sea turtles and Hawaiian monk seals. For anything other than a humpback, leaders count every animal as an adult and don’t try to separate calves. Monk seal sightings also go to NOAA Fisheries at 1-888-256-9840.
For each hour, leaders rate fog, rain, haze, wind, foam, swell and glare on a visibility chart, and a data analyst assigns the visibility code later. Within one hour of the count, leaders submit the census numbers to the sanctuary by online form or phone, along with how many volunteers took part and how many members of the public stopped by.
The sanctuary publishes those numbers as preliminary data on oceancount.org’s results page: whales per 15-minute period at each site, written as adults/calves, plus an average per 15-minute period for each island.
What volunteers record on the behavior sheet
General volunteers fill in the Behavior Sheet, and the sanctuary suggests working in pairs: one person watches and calls out what the whales do, the other writes it down, and the two can swap. The sheet runs in half-hour blocks from 0800-0830 to 1131-1200. Volunteers note the number of adults and calves they can see, then add a bar every time a whale breaches, slaps, blows or dives.
At the end of each half hour, volunteers total the bars in each column and circle the number. Anyone who takes a break writes down that they were away, so the missed time isn’t recorded as a half hour with no whales.
The back of the sheet has the same hourly visibility chart as the census, and there’s space for comments on anything the columns don’t cover. Our behavior glossary takes each column and comment term in turn, with the sanctuary’s definition and what it looks like from shore.
A third sheet, the site map, is now optional: oceancount.org’s resources page says it hasn’t been required since 2024. Where a site still does it, two volunteers draw the site between 10:30 and 11:00, mark every group of whales and estimate its distance with a ruler held at arm’s length against the horizon and a table keyed to the site’s elevation. The late Leon Brenaman developed that distance tool in 2001, according to the sanctuary’s prep document.
Site leaders and volunteers
Site leaders are chosen for each site before a mandatory training session, where they learn the count method and collect the materials for count day. During count week they receive their volunteer list from the program coordinator. On the morning they give a short background on the sanctuary and the whales and show volunteers how to sight whales and fill in the sheets.
Every volunteer reads a Notice of Caution and signs in. The notice limits the approved tasks to the behavior sheet, the site map and the site leader’s instructions, and it says volunteers must never enter the water during the count. Some sites sit on high cliffs and others on low rocks with surf, and the leader can call the count off if the weather turns. At the end, leaders collect the sheets, check them for legibility and star the two most accurate behavior sheets.
How to join the 2027 count
Registration happens only on the program’s own site, at oceancount.org/registration. Each count has its own window, opening on the first Monday of that month at noon Hawaiʻi time and closing two weeks later. You register each person separately for each date, children included, and a form submitted without a site doesn’t register you. These are the 2027 windows as posted on that page when we checked it on September 25, 2026.
| Count date | Registration opens (noon HST) | Registration closes (noon HST) |
|---|---|---|
| Saturday, January 30, 2027 | Monday, January 4 | Monday, January 18 |
| Saturday, February 27, 2027 | Monday, February 1 | Monday, February 15 |
| Saturday, March 27, 2027 | Monday, March 1 | Monday, March 15 |
Each site has a volunteer limit, set by its access permit and the space available, and the program handles large groups case by case. Questions about sites or registration go to the Ocean Count team through their contact page.
The site leader guide lists what to bring: a hat, sunglasses, sunscreen, water, a watch, a clipboard and pens or pencils. Binoculars or a spotting scope help but aren’t required, and a beach chair or mat and rain gear are optional. Your site leader sets the meeting time, which the guide puts at 7:30 am or earlier, half an hour before the first scan.
What the count data is used for
The sanctuary’s site leader guide says the census “does not claim to provide scientifically accurate results” and serves to supplement other research, while giving some information on how whales use inshore waters on an average peak-season day. The same guide says the count serves to promote public awareness about humpback whales, the sanctuary and shore-based whale watching.
The daily totals the sanctuary announces are sums of every tally, so the same whale can appear more than once. NOAA’s recap of the 2026 season reported 4,325 humpbacks observed across both counts and all three dates, Ocean Count and the Great Whale Count together, and noted that the figure “may represent duplicate sightings of the same koholā” (humpback whales) by different observers, at different times or from different sites. The per-period island averages on the results sheets are the better measure for comparing one count with another.
Since 2019 the sanctuary has combined its data with the Great Whale Count on Maui for a statewide view, and the 2026 recap links an interactive map by Dr. Anke Kügler that tracks both counts over the past 12 years. Site leaders collect the behavior sheets, but the January 31, 2026 preliminary results sheet states that the behavioral data “is not part of this report.” To ask about that data, contact the sanctuary.
How Ocean Count differs from the Great Whale Count on Maui
Maui and Lānaʻi aren’t Ocean Count islands. There, the nonprofit Pacific Whale Foundation runs its own Great Whale Count, which it dates back to 1995, and in 2026 it had 12 sites on Maui and one on Lānaʻi. The two counts have been coordinated on the same days since 2019, and the foundation lists its 2027 counts for January 30, February 27 and March 27.
The two counts have separate registration. The foundation’s Great Whale Count page says its 2027 registration opens December 14, 2026, three weeks before Ocean Count’s first window, and it asks volunteers to stay from 8 am to noon. It doesn’t lend binoculars. To count on Maui or Lānaʻi, register with the foundation. For Oʻahu, Kauaʻi, Molokaʻi or Hawaiʻi Island, use oceancount.org.
This site is independent and not affiliated with NOAA, the sanctuary or the Ocean Count program. The method on this page is our summary of the sanctuary’s published data sheets and site leader guide, which are on oceancount.org/resources.