The verdict
Best places to dive with common threshers
Alopias vulpinus
The most reliable place to dive with common threshers is Channel Islands, from August to September.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| January: 1 of 7 at peak | February: 1 of 7 at peak | March: 2 of 7 at peak | April: 3 of 7 at peak | May: 1 of 7 at peak | June: 0 of 7 at peak | July: 0 of 7 at peak | August: 3 of 7 at peak | September: 3 of 7 at peak | October: 1 of 7 at peak | November: 1 of 7 at peak | December: 0 of 7 at peak |
Most sites at peak Some at peak Possible only
Based on 3,125 OBIS records of common thresher (Alopias vulpinus) within 60 km of 7 dive destinations.
Top destinations to dive with common threshers
Ranked on how reliably they turn up, then on how long the record runs.
| # | Destination | Country / area | Season | Reliability | Evidence | Dive type |
|---|---|---|---|---|---|---|
| 1 | Channel Islands | USA | Aug–Sep | Near-guaranteed | 26 of 32 years | Liveaboard, Day boat |
| 2 | Monterey | USA | Aug–Oct | Near-guaranteed | 26 of 32 years | Shore |
| 3 | Outer Banks | USA | Feb, Apr | Hit-or-miss | 3 of 32 yearsfew records | Day boat |
| 4 | Aliwal Shoal | South Africa | Mar | Hit-or-miss | 2 of 31 yearsfew records | Day boat |
| 5 | Protea Banks | South Africa | Mar | Hit-or-miss | 1 of 26 yearsfew records | Day boat |
| 6 | Catalina Island | USA | Apr, Nov | Hit-or-miss | 4 of 32 yearsfew records | Shore, Day boat |
| 7 | Poor Knights | New Zealand | Jan, Apr–May, Aug–Sep | Hit-or-miss | 7 of 31 yearsfew records | Day boat |
When to dive with common threshers
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Channel Islands | Jan: Not common | Feb: Not common | Mar: Not common | Apr: Not common | May: Not common | Jun: Not common | Jul: Possible | Aug: Peak season | Sep: Peak season | Oct: Possible | Nov: Possible | Dec: Possible |
| Monterey | Jan: Not common | Feb: Not common | Mar: Not common | Apr: Not common | May: Not common | Jun: Not common | Jul: Possible | Aug: Peak season | Sep: Peak season | Oct: Peak season | Nov: Not common | Dec: Not common |
| Outer Banks | Jan: Not common | Feb: Peak season | Mar: Not common | Apr: Peak season | May: Possible | Jun: Not common | Jul: Not common | Aug: Not common | Sep: Not common | Oct: Not common | Nov: Not common | Dec: Not common |
| Aliwal Shoal | Jan: Not common | Feb: Not common | Mar: Peak season | Apr: Not common | May: Not common | Jun: Not common | Jul: Not common | Aug: Not common | Sep: Not common | Oct: Not common | Nov: Not common | Dec: Not common |
| Protea Banks | Jan: Not common | Feb: Not common | Mar: Peak season | Apr: Not common | May: Not common | Jun: Not common | Jul: Not common | Aug: Not common | Sep: Not common | Oct: Not common | Nov: Not common | Dec: Not common |
| Catalina Island | Jan: Not common | Feb: Not common | Mar: Not common | Apr: Peak season | May: Possible | Jun: Possible | Jul: Not common | Aug: Not common | Sep: Not common | Oct: Not common | Nov: Peak season | Dec: Not common |
| Poor Knights | Jan: Peak season | Feb: Not common | Mar: Possible | Apr: Peak season | May: Peak season | Jun: Possible | Jul: Possible | Aug: Peak season | Sep: Peak season | Oct: Not common | Nov: Possible | Dec: Not common |
Peak season Possible Not common
Common thresher month by month
- January
- The one peak month at Poor Knights.
- February
- The one peak month at Outer Banks.
- March
- The one peak month at Aliwal Shoal. Also good at Protea Banks.
- April
- The one peak month at Outer Banks. Also good at Catalina Island and Poor Knights.
- May
- Last peak month at Poor Knights.
- June
- Off-peak everywhere. Your best chance is Catalina Island.
- July
- Off-peak everywhere. Your best chance is Channel Islands.
- August
- Season starts at Channel Islands. Also good at Monterey and Poor Knights.
- September
- Last peak month at Channel Islands. Also good at Monterey and Poor Knights.
- October
- Last peak month at Monterey.
- November
- The one peak month at Catalina Island.
- December
- Off-peak everywhere. Your best chance is Channel Islands.
What to expect in the water
Water temperature and the suit to pack at the top sites, in the months common threshers are there.
| Destination | Season | Water | Suit |
|---|---|---|---|
| Channel Islands | Aug–Sep | 20 °C | 5 mm with hood and gloves |
| Monterey | Aug–Oct | 15–16 °C | 7 mm semi-dry |
| Outer Banks | Feb, Apr | 18–20 °C | 7 mm semi-dry |
| Aliwal Shoal | Mar | 26 °C | 3 mm full suit |
| Protea Banks | Mar | 27 °C | 3 mm full suit |
What else you'll see with common threshers
Animals at their peak in the same places and months.
Ocean sunfish
At Channel Islands, Monterey and Catalina Island
Blue shark
At Channel Islands, Monterey and Catalina Island
Sardine
At Channel Islands, Monterey and Catalina Island
California sea lion
At Channel Islands, Monterey and Catalina Island
Sand tiger shark
At Outer Banks and Aliwal Shoal
Blue whale
At Monterey
Diving with common threshers: common questions
- Where is the best place to dive with common threshers?
- The most reliable place to dive with common threshers is Channel Islands, from August to September.
- When is the best time to dive with common threshers?
- April, August to September, when 3 of the 7 best-evidenced destinations are at their peak. It varies by place: Channel Islands peaks August to September; Monterey peaks August to October; Outer Banks peaks February, April.
- What wetsuit do you need to dive with common threshers?
- At Channel Islands from August to September, the water is 20 °C to 20 °C, so bring a 5 mm with hood and gloves.
- How many places can you dive with common threshers?
- besttimetodive.com has common threshers on record at 7 of the destinations it scores. Not an exhaustive list — these are the sites we hold verified data for.