University of Maryland Center for Environmental ScienceHorn Point Oyster Hatchery

Spat-on-Shell Sales

To place an order for spat-on-shell oysters, please contact Stephanie Alexander (UMCES HPL) at (410)221-8310 or, or ORP at (410)990-4970.


The time it will take for your order to be ready will vary, but the hatchery will try to accommodate reasonable setting schedules. Custom spawns will require a non-refundable 50% deposit (product price only, excludes shipping etc.) when the order is placed. Any spawn requiring specific broodstock or ploidy manipulation are considered custom spawns. Custom spawns will only be produced in a limited time frame. Payments can be made to UMCES HPL by check or to ORP by credit card, check, or money order. Cash will not be accepted. All sales MUST BE PAID IN FULL before product will be released/shipped. Personal checks will not be accepted for orders over $500 without prior approval. A certified check, money order, or credit card is required.

Orders for Pick-up

Once notice is given that your spat on shell order is ready, you will have 7 business days to pick up your order. If pick-up is not made within those 7 days, you will forfeit your order and product availability will not be guaranteed. Orders MUST BE PAID IN FULL AT TIME OF PICK-UP.

Orders for Delivery

Once notice is given that your larvae order is ready, you will be given a total balance due that includes product and shipping fees. Please mail your payment to UMCES HPL or ORP. When full payment is received, a hatchery staff member will assist with scheduling a shipment of your order via Fed Ex. You will have 7 business days in which to schedule shipping of your order. Failure to schedule/receive shipment within this time frame could result in an increase in price and product availability is not guaranteed. We do not ship on Fridays or weekends.

There are 2 shipping options; 1. You pay a separate invoice for shipping after FedEx calculates costs billed by HPL monthly/seasonally, or  2.  you obtain your own FedEx account number and are billed directly from FedEx.


In the event that the facility is unable to fulfill your order, you will be refunded your deposit (if applicable). This can take up to 6-8 weeks to process.

Sos in Hand

Spat-on-Shell (per thousand)

Size Diploid Wild Diploid Disease Resistant* or Triploid Disease Resistant*
< 5 mm $9.50 $12.00
5-10 mm***** $13.50 $17.00

*Mandatory royalty fees for disease resistant and triploid oyster have been included in the prices above.

*****Seed and spat on shell larger than 5mm will not be readily available. It is possible we may have larger sizes available in the latter part of the summer. If you are interested please provide your contact information. These will be sold on a first come first served basis. Please note these quantities will be limited.

Spat-on-Shell (bulk orders)

Size Cost for Diploid Wild
<5mm $3,500.00 per million

Delivery fees may apply
Contingent upon growing season and availability of planting vessel.