Announced by the USPS on October 24, 2022.
Under the Endangered Species Act, which marks its 50th anniversary in 2023, more than 1,300 imperiled plant and animal species are safeguarded to increase their chances of survival. With this pane of 20 stamps, the Postal Service presents a photographic portfolio of 20 representative endangered animal species. Those featured are found within the 50 states and U.S. territories and possessions or living near U.S. borders. The images are among more than 13,000 in photographer Joel Sartore’s “Photo Ark,” his project to document as many animal species as possible. Art director Derry Noyes designed the stamps with Sartore’s existing photographs.
New information will appear below the line, with the most recent at the top.
Updated July 1st
Here are the Scott catalogue numbers for this issue:
5799 Pane of 20
a. (63¢) Laysan teal
b. (63¢) Black-footed ferret
c. (63¢) Roanoke logperch
d. (63¢) Thick-billed parrot
e. (63¢) Candy darter
f. (63¢) Florida panther
g. (63¢) Masked bobwhite quail
h. (63¢) Key Largo cotton mouse
i. (63¢) Lower Keys marsh rabbit
j. (63¢) Wyoming toad
k. (63¢) Vancouver Island marmot
l. (63¢) Golden-cheeked warbler
m. (63¢) Guam Micronesian kingfisher
n. (63¢) San Francisco garter snake
o. (63¢) Mexican gray wolf
p. (63¢) Attwater’s prairie chicken
q. (63¢) Nashville crayfish
r. (63¢) Piping plover
s. (63¢) Desert bighorn sheep
t. (63¢) Mississippi sandhill crane
u. As No. 5799, imperforate
v. As No. 5799a, imperforate
w. As No. 5799b, imperforate
x. As No. 5799c, imperforate
y. As No. 5799d, imperforate
z. As No. 5799e, imperforate
aa. As No. 5799f, imperforate
ab. As No. 5799g, imperforate
ac. As No. 5799h, imperforate
ad. As No. 5799i, imperforate
ae. As No. 5799j, imperforate
af. As No. 5799k, imperforate
ag. As No. 5799l, imperforate
ah. As No. 5799m, imperforate
ai. As No. 5799n, imperforate
aj. As No. 5799o, imperforate
ak. As No. 5799p, imperforate
al. As No. 5799q, imperforate
am. As No. 5799r, imperforate
an. As No. 5799s, imperforate
ao. As No. 5799t, imperforate
Updated April 24th
Here are the first-day postmarks for this issue:
The Digital Color Postmark measures 2.04″ x 1.0″ 
The pictorial postmark measures 2.39″ x 1.0″
Updated April 21st from the Postal Bulletin
On May 19, 2023, in Wall, SD, the United States Postal Service® will issue the Endangered Species stamps (Forever® priced at the First-Class Mail® rate) in 20 designs, in a pressure-sensitive adhesive (PSA) pane of 20 stamps (Item 483800). These stamps will go on sale nationwide May 19, 2023, and must not be sold or canceled before the first-day-of-issue. The Endangered Species commemorative pane of 20 stamps must not be split and the stamps must not be sold individually.
Featuring 20 different endangered animals, these 20 stamps pay tribute to the Endangered Species Act and mark the 50th anniversary of the legislation. The stamp art showcases photographs of endangered animals found within the 50 states and American territories and possessions, as well as 
two North American species living near U.S. borders. The images are among more than 13,000 in photographer Joel Sartore’s “Photo Ark,” his project to document as many animal species as possible. Art director Derry Noyes designed the stamps with Sartore‘s existing photographs.
No automatic distribution.
How to Order the First-Day of Issue Postmark:
Customers have 120 days to obtain the first-day-of-issue postmark by mail. They may purchase new stamps at their local Post Office™ or at The Postal Store® website at store.usps.com/store/home. They must affix the stamps to envelopes of their choice, address the envelopes (to themselves or others), and place them in a larger envelope 
addressed to:
FDOI – Endangered Species Stamps
USPS Stamp Fulfillment Services
8300 NE Underground Drive, Suite 300
Kansas City, MO 64144-9900
After applying the first-day-of-issue postmark, the Postal Service will return the envelopes through the mail. There is no charge for the postmark up to a quantity of 50. There is a 5-cent charge for each additional postmark over 50. All orders must be postmarked by September 19, 2023.
Technical Specifications:
Issue: Endangered Species Stamps
Item Number: 483800
Denomination & Type of Issue: First-Class Mail Forever
Format: Pane of 20 (20 designs)
Series: N/A
Issue Date & City: May 19, 2023, Wall, SD 57790
Art Director: Derry Noyes, Washington, DC
Designer: Derry Noyes, Washington, DC
Existing Photos: Joel Sartore
Modeler: Sandra Lane / Michelle Finn
Manufacturing Process: Offset, Flexographic
Printer: Banknote Corporation of America
Press Type: Gallus 74
Stamps per Pane: 20
Print Quantity: 30,000,000 stamps
Paper Type: Phosphor Tagged Paper, Block
Adhesive Type: Pressure-sensitive
Colors: Cyan, Magenta, Yellow, Black, Opaque White
Stamp Orientation: Horizontal
Image Area (w x h): 1.42 x 1.085 in / 36.068 x 27.559 mm
Overall Size (w x h): 1.56 x 1.225 in / 39.624 x 31.115 mm
Full Pane Size (w x h): 7.48 x 9.0 in / 189.992 x 228.60 mm
Press Sheets Size (w x h): 14.96 x 18.00 in / 379.984 x 457.20 mm
Plate Size: 80 stamps per revolution
Plate Number: “B” followed by five (5) single digits
Marginal Markings:
Front: Header: Endangered Species • Plate number in two corners of the pane
Back: ©2022 USPS • USPS logo • Two barcodes (483800) • Plate position diagram (4) • Promotional text
[ceremony details] [click on any of the pictures for larger versions]
Postal Service Spotlights Endangered Species
What: The U.S. Postal Service will commemorate the 50th anniversary of the Endangered Species Act (ESA) by issuing a pane of stamps featuring 20 photos of different 
endangered animals.
The first-day-of-issue event for the Endangered Species Forever stamps is free and open to the public.
News of the stamps is being shared with the hashtags #EndangeredSpeciesStamps and #ESA50.
Who: Peter Pastre, vice president, government relations and public policy, USPS
Martha Williams, director, U.S. Fish and Wildlife Service
Joel Sartore, National Geographic Explorer and photographer
When: Friday, May 19, 2023, at 11 a.m. MT
Where: National Grasslands Visitor Center
708 Main St., Wall, SD 57790
https://www.fs.usda.gov/recarea/nebraska/recarea/?recid=10639
RSVP: Dedication ceremony attendees are encouraged to RSVP at usps.com/endangeredspecies
Background: The stamps showcase photographs of endangered animals found within the 50 states and U.S. territories, as well as two North American species living near U.S. 
borders.
The 20 images are from thousands in National Geographic Explorer and photographer Joel Sartore’s “National Geographic Photo Ark,” a project to document every species living in the world’s zoos, aquariums and wildlife sanctuaries, inspire action through education, and help protect wildlife by supporting on-the-ground conservation efforts.
On Dec. 27, 1973, President Richard Nixon signed the ESA into law, following a unanimous Senate vote. In the 50 years since, other nations worldwide have emulated the 
pioneering U.S. initiative. The ESA provides a framework to conserve and protect endangered and threatened species and their habitats both domestically and abroad.
Under the ESA, more than 1,670 U.S. species and 698 foreign species are safeguarded to increase their chances of survival. Scientists estimate that hundreds of species have been rescued from the brink of extinction in the United States since the ESA began. A species found to need protection is listed under the ESA as either threatened or endangered, the latter defined as “in danger of extinction throughout all or a significant portion of its range.”
Updated January 10th:
These stamps will be issued Friday, May 19, in Wall, SD. The National Grasslands Visitor Center, part of the Buffalo Gap National Grassland, is in Wall. The center features exhibits about grassland wildlife and plants, grazing management and the history of the Great Plains.
What do Vancouver Island marmot and Mexican gray wolf doing on US stamps?🤔
I don’t speak for the USPS, but I don’t think wild animals observe political borders. That is, you can probably find both the marmot and the wolf in the U.S.
Technically, Timber wolves are endangered too, as well as American gray wolf. I might be wrong, but the last time I checked it was on that list.🤔
So the Florida Grey Wolf is now augmented by the Florida Grey Cougar? ( Does she drive a Lincoln Continental? )
Sorry, just checked, they are under Threatened now.
https://vancouverisland.ctvnews.ca/vancouver-island-marmot-to-be-featured-on-u-s-postal-stamp-1.6144141
About Half-way between Wall SD, and Sturgis SD ( Aug 04 – 13 ) is Ellsworth Air Force Base. For those with a Military I.D., good camping and reasonably-priced accommodations. )
From USA Philatelic 2023 Volume 28 2nd Quarter, USPS# 4838xx #04 Pn-20 $12.60, #06 Press Sheet With die cuts $50.40, #08 Press-Sheet WithOut die cuts $50.40, #16 FDC-20 $23.60, #21 DCP-20 $40.60.
Virtual FDoI : https://www.facebook.com/USPS/videos/1719587825140898
Similar to the Railroad Anniversary stamps, a Limited Edition (4000) Collector’s Set with Progressive Stamp Proofs, Final Edition in Pn-20, Numbered Cert. of Authen. #483899 $59.95 ( Limit of 5 per order )
I received an “Endangered Species” Desert Bighorn Sheep stamp in the mail this week on the envelop containing the announcement for our Stamp Club’s October meeting. The first thing that I noticed about the cancellation was that it was a hand canceled which is very unusual. The cancel was circular and most of it was unreadable because the stamp is so dark. What was readable on the cancel was the word “REGISTRY”. I thought maybe the person that mails our bulletins had asked the clerk ant the post office to hand cancel the envelops but she said she just dropped them in the box. I took the envelop back to the Post Office and asked the clerk if he knew what the cancellation was and what he could tell me about it, He said he had never seen anything like it. When I shared this at our meeting it was conjectured that maybe the special coating on the animal portion of the stamp would not take the ink of the machine cancel and it was hand cancelled to make sure a portion of the stamp received ink but I receive mail regularly that is not cancelled at all. Just wondered if anyone had run into this on these stamps and had an explanation for what is going on?
In some large cities, there are (or at least were) “registry stations” to process such mail. They weren’t actual physical locations, beyond maybe a desk or a section of a counter, if that much. It’s possible that the post office where the announcement was mailed had some of its mail process at that “desk” and the clerk used that station’s cancel.
Perhaps a dumb question but I will ask anyway – what makes a stamp like this, which is less than 5 months old, unavailable to be ordered from the USPS.gov site?
Is there any way to tell at / around release time, if a stamp will go off sale in a
shorter period of time than “normal”?
I can still get every other stamp from January onward, and some from last year or older, but this one is no longer available.
Thank you!
There are a couple of possibilities: One, it’s a glitch on the USPS website, which might be temporary. Another is that the stamp set proved more popular than the USPS anticipated and it sold out quickly. (The FDCs are still available.) Under “Technical Specifications” on this issue’s page, the USPS says it was producing/had produced “30,000,000 stamps.” At 20 stamps per sheet, though, that’s only 1.5 million sheets (panes). For Waterfalls, a month later, the quantity is 34,992,000, which my calculator translates to just under 3 million panes of 12. A week earlier, 18 million Chief Standing Bear stamps were issued. That, however, is a single-design issue.
Retailers will tell you predicting how many of an item you’ll sell is one of the hardest parts of selling.