1 Current CTD-Satellite Relay Data Logger (CTD-SRDL) with CTD
head (black) based on an inductive cell (2). Bottom left picture
shows a CTD-SRDL deployed on a Southern elephant seal at the
beginning of the deployment. Top right picture shows an instrument
on a Weddell seal after several months. The antenna is kinked
because of repeated bending when the seal is moving through its
breathing hole. Integration of a miniaturized conductivity sensor
into an animal-borne instrument. Boehme L. 1, Lovell P. 2, Morris
A. 3 and Pascal R. 3 1 Scottish Oceans Institute, University of St
Andrews [email protected] 2 SMRU Instrumentation Group,
University of St Andrews 3 National Oceanography Centre,
Southampton Relating marine mammal movements and behaviour to
fine-scale ocean structure requires oceanographic information on
similar spatial and temporal scales. The appropriate environmental
information is usually not readily available especially in high
latitude oceans. One way to solve this mismatch is to deploy
oceanographic sensors on the animals themselves to obtain in-situ
information without any spatial or temporal lag. 1.antenna
2.temperature probe 3.inductive cell 4.pressure sensor 5.battery
6.communications port 7.wet-dry sensor The aim of this project is
to modify and improve an existing miniature
conductivity-temperature sensor and incorporate it into the proven
design of a Satellite Relay Data Logger. A reduction in the size of
the oceanographic sensor would enable us to add other sensors and
use other telemetry systems without increasing the package size.
The use of an electrode instead of a inductive cell will reduce the
effect of nearby objects on the conductivity measurements (Boehme
et al., 2009) Slide 2 2 Integration of a miniaturized conductivity
sensor into an animal-borne instrument. References Boehme, L., P.
Lovell, M. Biuw, F. Roquet, J. Nicholson, S. E. Thorpe, M. P.
Meredith, and M. Fedak (2009), Technical Note: Animal-borne CTD-
Satellite Relay Data Loggers for real-time oceanographic data
collection, Ocean Science, 5(4), 685-695. Huang, X., R. W. Pascal,
K. Chamberlain, C. J. Banks, M. Mowlem, and H. Morgan (2011), A
Miniature, High Precision Conductivity and Temperature Sensor
System for Ocean Monitoring, Ieee Sens J, 11(12), 3246-3252. In
this study, we modified an existing miniature
conductivity-temperature sensor of about 10x10mm (Huang et al.,
2011) nad designed a new control board to deliver temperature and
conductivity measurements via an I 2 C interface. Three miniature
sensors (left) and one sensor with new control board (right) ready
to be interfaced with a SRDL. Design studies for new animal-borne
instruments using the miniature sensor. GPS/Iridium-CTD-SRDL (left)
and cetacean SRDL for barb attachment (left) Current animal-borne
instruments using an inductive cell to measure the salinity of the
surrounding water need a rigid attachment, which is normally only
possible when the animal can be restrained during the attachment
procedure limiting their use to seals and small cetaceans. This new
sensor is not influenced by the attachment method and would
therefore be able to provide accurate measurements while rotating
around a barb attachment as is used to tag large cetaceans. The
sensor is currently undergoing lab and field tests to determine the
accuracy and effect of bio-fouling on the sensors reliability. This
methodology provides for ecosystem studies of a range of marine
animals (e.g. large cetaceans, fish, birds) that are not currently
feasible.