Dr. Geoffrey Smith
NWFSC Biology Instructor
For Floridians, this fish may be the only snow we see throughout the year. The Snowy Grouper earns its common name from the many small to medium sized white spots on its side. Other than these white spots, which are most noticeable in juveniles, the body is generally a gray to brown coloration (Figure 1). In additional to the white spots, juveniles may also have a dark saddle on the region where the caudal (tail) fin joins the body (Figure 1). This section of the fish is known as the caudal peduncle. Juvenile Warsaw Grouper Hypothodus nigritus may be confused with Snowy Grouper as they are also generally gray with white spots on their sides, although the spots tend to be a bit smaller and more irregular in placement. However, the Warsaw Grouper can be easily distinguished from Snowy Grouper by looking at the spines on the dorsa fins. Not only will Warsaw Grouper have one less spine (10 vs 11), their second and third dorsal spines are greatly enlarged compared to the spines. Warsaw Grouper also reach much larger sizes than Snowy Grouper (over 300 lbs vs less than 100 lbs). Both the Snowy and Warsaw Groupers are considered deepwater groupers with adults typically inhabiting waters of 300 ft or more. Juveniles, especially those that have recently settled out of their planktonic stage are commonly found in shallower depths and migrating further offshore as they grow. Snowy Grouper are found in these deep depths from Massachusetts southward along the Atlantic coast to Brazil, including all of the Gulf of Mexico and Caribbean (Figure 2). Like many groupers, Snowy Grouper are protogynous hermaphrodites meaning that they typically begin life and mature as females before transitioning to become males. They first mature as females around 5-6 years of age and transition to become males sometime between 7 and 13 year of age, with a maximum estimated age of 34 years. As with many sequential (one sex then then switching to the other at some size/age) hermaphrodites, management of Snowy Grouper (and most other grouper species) can be difficult. Harvest typically removes the largest individuals (males in this case) first, reducing the numbers of that sex. This can result in scenarios where there may be many mature females but few to no males to fertilize their eggs, or it can cause a biological shift to mature and transition earlier which can result in fewer eggs being produced per individual because of their smaller size. If you plan to target this species recreationally, there is a 4 per person bag limit that is part of the overall grouper aggregate for a person. There is no minimum size limit currently in place (mostly due to the extreme barotrauma, pressure release trauma, experienced when these fish are brought up from deep depths). There is also currently no closed season for this species.
Figure 1: Typical coloration of a young Snowy Grouper (Photo credit: Cláudio Dias Timm, https://fishbase.org).
Figure 2: Distribution of Snowy Grouper within the Gulf of Mexico and along the Caribbean, note their range extends northward to Massachusetts and southward to Brazil (https://biogeodb.stri.si.edu/caribbean).
