In this paper we present Blip, a system for boat identification that uses the existing Internet of Things (IoT) network of sensors deployed inside a smart marina. Blip combines the data from two types of commercial low-power wireless sensors: Falco Presence and Falco Boat. The former is deployed on the pontoons, to detect boats that dock at the slips. The latter is installed inside the boats' cabins to monitor various parameters and trigger an alarm in case of: intrusion, fire, shock and tilt. To identify a boat, we fuse the boat presence events from the Falco Presence devices and the health reports from a Falco Boat. The health reports contain information about nearby Falco Presence devices and their received signal strength (known as Received Signal Strength Indicator or RSSI). When a boat enters the marina, Falco Boat joins the network and starts sending health reports. Initially, Blip estimates the slip location assigning the boat to the slip where a Falco Presence has the strongest RSSI. Then, Blip selects the closest slip to it, which changed to occupied in a given time window. We validate our system using a historical dataset from a marina over a period of 4 months. Every slip in the marina is equipped with a Falco Presence device, and 8 boats are equipped with a Falco Boat device. The results show that the Blip system identifies boats upon entering the marina with 100 % accuracy. The main advantage of the Blip system is that it provides location-aware service to the marina without any additional cost or hardware deployments.