Here's a thought....
Delta and Richmond are home to large composting facilities. Composting operations are taking in more and more municipal food waste (diverted from landfills). Yard waste, mostly due to contamination can, and often does, contain high levels of lead. When food and yard waste are combined, lead finds it way into food waste. Poor vector attraction reduction practices can easily cause high levels of lead in rats, seagulls, etc...
Few if any people glance at a dead or dying rat, but if it's a dead or dying eagle....different response.
Food waste attracts rats, seagulls, mice, crows etc... Eagles/raptors feast on them (especially during winter and cold springs when conventional food sources are scarce) and are becoming more prevelant at composting facilities because of the inclusion of food waste in the waste stream.
Composting is a wonderful thing when done right, and I'm not suggesting it shouldn't be done, or that it is the cause of this. Just throwing out some food for thought (pun intended).
Always easy to blame hunters, especially in a "news" article rife with "could be" and "may be".....
http://www.cbc.ca/news/canada/britis...lity-1.3960676
https://www.bostonglobe.com/lifestyl...wrJ/story.html
http://www.newmoa.org/events/docs/53...ostNov2012.pdf