CartoDB CSS and SQL to visualize flight tracks of gull Eric grouped by seasonal behaviour in Torque. Expressing the seasonal behaviour as a number allows Torque to differentiate between those.

ericFlightPathsTorque.css

/** torque visualization */

Map {
-torque-frame-count:512;
-torque-animation-duration:40;
-torque-time-attribute:"date_time";
-torque-aggregation-function:"avg(behaviour_number)";
-torque-resolution:1;
-torque-data-aggregation:linear;
}

#bird_tracking{
  comp-op: multiply;
  polygon-opacity: 0.8;
  line-color: #ffffff;
  line-width: 1;
  line-opacity: 1;
  marker-opacity: 0.9;
  marker-line-color: #ffffff;
  marker-line-width: 0.5;
  marker-line-opacity: 1;
  marker-type: ellipse;
  marker-width: 3;
  marker-fill: #b81609;
  [value >= 2] { marker-fill: #ff9900; }
  [value >= 3] { marker-fill: #2167ab; }
}
#bird_tracking[frame-offset=1] {
 marker-width:5;
 marker-opacity:0.45; 
}
#bird_tracking[frame-offset=2] {
 marker-width:7;
 marker-opacity:0.225; 
}

ericFlightPathsTorque.sql

SELECT
  cartodb_id,
  the_geom,
  the_geom_webmercator,
  date_time,
  CASE 
    WHEN date_time >= '2013-05-28' AND date_time < '2013-06-25' THEN 1
    WHEN date_time >= '2013-06-25' AND date_time < '2013-07-24' THEN 2
    ELSE 3
END as behaviour_number
FROM bird_tracking
WHERE
  device_info_serial = 851
  AND userflag IS FALSE
  AND date_time >= '2013-05-17'
  AND date_time < '2013-12-19'