It's not quite an emergency yet, but science-fiction and fantasy on network television could be in some trouble.

Audiences for shows such as "Lost" on ABC and "Heroes" on NBC were down just under 19 percent in 2009 compared to the year before. Of 10 shows that aired episodes in both 2008 and 2009, not a single one showed an audience increase, with one -- "Terminator: The Sarah Connor Chronicles" -- actually losing half its audience after being pushed to Fridays toward the end of its run.

Dropping 19 percent is not insignificant, but not enough to panic. Some declines were based on schedule changes, while others are definitely from audience erosion not just from other shows, but from other media platforms competing with genre programming.

Although "Sarah Connor" had the biggest year-over-year drop, the now-cancelled "Life on Mars" on ABC had a large fall in 2009 as well, losing 40 percent of its previous year audience. Although not as dramatic, "Lost" lived up to its name, losing just under 25 percent of its 2008 viewers, while "Heroes" dropped a little more than 23 percent.

The results were based on an Airlock Alpha survey of overnight ratings each show had in 2008 versus 2009.

Surprisingly, the one show that challenged or achieved the top of each year only lasted one season on CBS. That was "Eleventh Hour," an American remake of the British series that starred former "Star Trek: The Next Generation" actor Patrick Stewart. It finished with a 7.6 rating/13 share average in overnights in 2008, just slightly behind the 7.7/12 "Lost" earned for first place, but was tops in 2009 with a 7.1/12. "V" on ABC was a somewhat close second with a 6.7/10 after four episodes.

No genre show finished below a 2.0 household rating average in 2008, with "Supernatural" attracting the smallest audience with a 2.1/4. However, three shows finished below that threshold in 2009 led by the now-cancelled "Reaper" on The CW with a 1.4/2 followed by "Supernatural" with a 1.8/3 and "Dollhouse" on Fox with a 1.9/3.

New shows are doing well in 2009, for the most part. "V" and "FlashForward" on ABC were the second and third most-watched genre programs this past year while the short-lived CBS series "Harper's Island" finished with a 5.7/10 before it was banished to Saturdays (a day not tracked by Airlock Alpha).

The failed "Kings" on NBC finished in 11th place with a 3.2/5 before its exile to Saturdays, while "Vampire Diaries" finished the best of any CW show either year (tying with "Smallville" in 2008) with a 2.5/4, good enough for 12th place.

Top Network Genre Shows (2008) -- [Audience Loyalty Index rating]
1. Lost (ABC) -- 7.7/12 -- [81.2]
2. Eleventh Hour (CBS) -- 7.6/13 -- [86.8]
3. Life on Mars (ABC) -- 6.0/10 -- [77.3]
4. Fringe (Fox) -- 5.9/9 -- [71.4]
5. New Amsterdam (Fox) -- 5.3/8 -- [63.4]
6. Moonlight (CBS) -- 5.1/9 -- [97.1]
7. Heroes (NBC) -- 5.1/8 -- [82.9]
8. Dexter (CBS) -- 4.5/8 -- [86.3]
9. Terminator: The Sarah Connor Chronicles (Fox) -- 4.3/7 -- [39.2]
10. Chuck (NBC) -- 4.1/6 -- [94.2]
10. Knight Rider (NBC) -- 4.1/6 -- [90.6]
12. Jericho (CBS) -- 3.9/7 -- [91.0]
13. Pushing Daisies (ABC) -- 3.5/6 -- [83.6]
14. Smallville (CW) -- 2.5/4 -- [86.3]
15. Supernatural (CW) -- 2.1/4 -- [82.7]
TOTAL -- 4.8/8 -- [62.1]

Top Network Genre Shows (2009) -- [Audience Loyalty Index rating]
1. Eleventh Hour (CBS) -- 7.1/12 -- [77.3] -- DOWN 1.3%
2. V (ABC) -- 6.7/10 -- [78.5]
3. FlashForward (ABC) -- 5.9/9 -- [76.0]
4. Lost (ABC) -- 5.8/9 -- [85.6] -- DOWN 24.7%
5. Harper's Island (CBS) -- 5.7/10 -- [84.6]
6. Fringe (Fox) -- 5.3/8 -- [68.5] -- DOWN 10.2%
7. Heroes (NBC) -- 3.9/6 -- [74.8] -- DOWN 23.5%
8. Chuck (NBC) -- 3.8/6 -- [78.3] -- DOWN 7.3%
9. Life on Mars (ABC) -- 3.6/6 -- [89.0] -- DOWN 40.0%
10. Knight Rider (NBC) -- 3.4/6 -- [90.6] -- DOWN 17.1%
11. Kings (NBC) -- 3.2/5 -- [78.5]
12. Vampire Diaries (CW) -- 2.5/4 -- [80.6]
13. Terminator: The Sarah Connor Chronicles (Fox) -- 2.2/4 -- [89.8] -- DOWN 48.8%
14. Smallville (CW) -- 2.0/3 -- [75.5] -- DOWN 20.0%
15. Dollhouse (Fox) -- 1.9/3 -- [69.2]
16. Supernatural (CW) -- 1.8/3 -- [83.3] -- DOWN 14.3%
17. Reaper (CW) -- 1.4/2 -- [86.4]
TOTAL -- 3.9/6 -- [52.0] -- DOWN 18.8%

Data collected from The Nielsen Co., as distributed by Zap2it. BlipNetwork tracks non-news, non-event programming, and figures for this story reflect airing of new episodes only. For more information on the Audience Loyalty Index, click here.