Alligator Gar water temperature range

[screaminleeman]

I have read of Alligator Gar being kept in outdoor ponds in the US. I was wondering what the winter low water temperature range for this species has been observed by outdoor pond fish keepers. Would Maryland ponds with spring feeds that never totally freeze over, but with winter temperatures ~ 45 degrees F support these rascles?

 

[Lepisosteus platyrhincus]

year round temp of 45? no. at that temp i believe they will stop eatting. they could prob surrive the winter at that temp but come spring and summer it needs to be warmer

 

[screaminleeman]

There are actually four underground springs, 1 very minor above ground spring and one large above ground spring that feed the pond. I had the pond dredged 7 years ago due to the accumulation of silt/ sediment from runoff. I had the stream running through my property dammed, and placed the pond fish into it while the major spring was diverted for the construction crew to work. A severe rainstorm washed out the dam and all original fish were lost.

The pond was dredged to a depth of 15 feet in dry areas and at least 5 feet around the perimeter and underground springs. I buried and landscaped a 120 gallon pond at the 6" spring feeder pipe to catch all entry water and "overflow through pond stone, pea pebble and sand into the main pond, which is around 200 feet across.

After the refill, the pond had 8 largemouth bass (two were missing the following year and another a third the second year) and around 25 - 30 Blue Gills. The Bluegill population is extremely well established, but the 8 original (5 remaining) LMB never mated and were originally ~ 8" seven years ago. They have got to be closing in on the end of their life expectancy. Mega quantities of Crayfish came to the pond on their own and are in extreme abundance. We also seined 100's of local minnows and stocked which have bred prolifically.

I take regular temperature reading which average 3 degree F difference from the spring entrance to the main pond outflow from late spring to early fall.

Typical temperature readings are 17 C ~ 62 F in April and max out in August @ around 21 C ~ 69 F.

The spring fills a five gallon bucket in a matter of seconds, and has NEVER run dry as long as I have been there (1979). The deepest freeze that I have witnessed in that time still had a surface area of ~ 30 foot radius around the spring entrance, and this has included week + durations of under 20 degrees, although that is extremely rare in Maryland.

I got my two Alligator Gars at ~ 2" last month, and they have already at least doubled in size. I was thinking 4 - 5 years before outgrowing my 135G, but holy cow it looks like I was off!

 

[E_americanus]

There are actually four underground springs, 1 very minor above ground spring and one large above ground spring that feed the pond. I had the pond dredged 7 years ago due to the accumulation of silt/ sediment from runoff. I had the stream running through my property dammed, and placed the pond fish into it while the major spring was diverted for the construction crew to work. A severe rainstorm washed out the dam and all original fish were lost.

The pond was dredged to a depth of 15 feet in dry areas and at least 5 feet around the perimeter and underground springs. I buried and landscaped a 120 gallon pond at the 6" spring feeder pipe to catch all entry water and "overflow through pond stone, pea pebble and sand into the main pond, which is around 200 feet across.

After the refill, the pond had 8 largemouth bass (two were missing the following year and another a third the second year) and around 25 - 30 Blue Gills. The Bluegill population is extremely well established, but the 8 original (5 remaining) LMB never mated and were originally ~ 8" seven years ago. They have got to be closing in on the end of their life expectancy. Mega quantities of Crayfish came to the pond on their own and are in extreme abundance. We also seined 100's of local minnows and stocked which have bred prolifically.

I take regular temperature reading which average 3 degree F difference from the spring entrance to the main pond outflow from late spring to early fall.

Typical temperature readings are 17 C ~ 62 F in April and max out in August @ around 21 C ~ 69 F.

The spring fills a five gallon bucket in a matter of seconds, and has NEVER run dry as long as I have been there (1979). The deepest freeze that I have witnessed in that time still had a surface area of ~ 30 foot radius around the spring entrance, and this has included week + durations of under 20 degrees, although that is extremely rare in Maryland.

I got my two Alligator Gars at ~ 2" last month, and they have already at least doubled in size. I was thinking 4 - 5 years before outgrowing my 135G, but holy cow it looks like I was off!

you may be able to get the gars to overwinter in the pond, but i wouldn't do it until they are at least 2' long or larger, this way they should at least have size on their side for surviving. over-winter mortality is extremely high in young of the year (YOY) fishes, and even smaller gars would struggle to some extent unless feed very well.

in a 135g (assuming 18" width) you might be able to get a year out of them...a 2' wide tank would give you more time, and a 3' wide tank would likely give you 2-3 years (more depending on growth of your individual fish). good luck--
--solomon