Birds Nest Pests?

tharbin · Mar 20, 2024

Hi,

I'm losing two Birds Nest corals but the damage looks to me more like the tissue is being eaten than a necrosis.

I've fragged off several of the still healthy tips hence the blunt ends. The green coral was growing nicely for the last several months other than a few small areas affected by low light. The light issue was fixed in January. I also have a pink birds nest which never settled in and grew at all. It is 95% gone with similar tissue loss.

I've watched the fish extensively and haven't caught any nipping of the coral nor do I see bite marks under magnification. I've tried searching but I haven't run across any information on birds nest pests. Part of what makes me think the problem may be a pest is that it seems like most of the loss occurs during lights out. I've looked the coral over as well as I can with a magnifier and haven't found any 'bugs'.

So that is a long way around of asking 'are there any common Seriatopora pests that I should be looking for? If it is just necrosis has anyone found an effective way to stop it? In the past I've had birds nest do well for years and suddenly crash and it always seemed that when it crashed, there was no saving it. I need to improve my husbandry of birds nest.

tharbin · Mar 20, 2024

Never mind on this. I was able to get a better look at what is going on it does look like STN. Now I just have to figure out what caused it. Flow has changed a little and phosphates crept up a little (.03 to .07) everything else is pretty much the same. I added a small skimmer but that was after the STN started.

Om84 · Mar 20, 2024

I had this happen to me a year or so ago. I dipped the birdsnest and saw a particular species of copepods. I posted about this around then. They looked gray in color. Other acros looked fine. I bought more birdsnest and they did well for a month and then their polyps would recede and I would see the same STN like scenario. I treated my tank with interceptor and have been able to grow them again without issues. I have never seen a pest that specifically targets birdsnest before. Try dipping your birdsnest and see what happens. If nothing comes off then you probably had a spike. They seem to be sensitive and among the first to be affected. I don’t know why people have called them hardy. I am able to keep all kinds of acros including high end pieces but birdsnest are not easy for me.

tharbin · Mar 20, 2024

Om84 said:
I had this happen to me a year or so ago. I dipped the birdsnest and saw a particular species of copepods. I posted about this around then. They looked gray in color. Other acros looked fine. I bought more birdsnest and they did well for a month and then their polyps would recede and I would see the same STN like scenario. I treated my tank with interceptor and have been able to grow them again without issues. I have never seen a pest that specifically targets birdsnest before. Try dipping your birdsnest and see what happens. If nothing comes off then you probably had a spike. They seem to be sensitive and among the first to be affected. I don’t know why people have called them hardy. I am able to keep all kinds of acros including high end pieces but birdsnest are not easy for me.

Thank you for this. copepods are not beyond the realm of possibility. I get most of my pods from @Eldredge and I trust his pods but I also buy local pods from time to time. I have had problems with local phyto once or twice so maybe pods.

I think I'll frag a chunk that looks like it is STNing and dip it to see what I get. One difference though is I'm still getting good polyp extension.

I agree with your assessment of birds nest, in fact I said much the same thing to my wife a few days ago. It grows well but every time one would go downhill it didn't stop until it was gone.

tharbin · Mar 24, 2024

As a follow up, I dipped the three frags I cut from the main colony in Revive and didn't find anything on them. I didn't pull the main colony (yet) to dip since I didn't find anything on the frags. As an experiment I cut the three frags at different distances from clearly damaged tissue. I cut one at about 1/4" from damage, one at about 1/2" from damage and one at about 3/4" from damage and mounted them all. So far, the ones cut at 3/4" and 1/2" look fine but the one cut at 1/4" is losing tissue. The loss on the main colony seems to have slowed down so I'm playing wait and see.

Main colony today:

The on cut at 1/4":

The one cut at 1/2" (the white near the base appears to be CA but...):

And the one cut at 3/4":

eroszhou0001 · Mar 25, 2024

It's obviously not eaten. It's peeling

eroszhou0001 · Mar 25, 2024

You get bite marks when you eat it

tharbin · Mar 25, 2024

eroszhou0001 said:
It's obviously not eaten. It's peeling

I agree. The reason I first asked was that under close observation there were no bite marks and there weren't any really obvious changes in flow, lighting or parameters. So I looked for some type of pest known to attack birds nest. I've been through AEF and MEN in previous tanks and the damage did resemble those (more like AEF than MEN) but I couldn't find a culprit. I've never had a coral actually peel before though.

The only thing I can think of is that I added a fuge around the same time frame I noticed the peeling starting and the addition of the fuge did raise the pH an average of around .05 over a period of a week or so but I don't think the pH had risen much if at all when I first noted the damage.

I don't really think that is the cause though as a week or two after I added the green birds nest, I acquired a frag of pink birds nest from the same grower. The green was already growing in the tank and looked very good. The pink never settled in and grew. It looked exactly the same for months. Both birds nests were sited in similar positions at opposite ends of the tank under very similar flow and lighting. The green grew well, the pink never grew at all that I could see.

A little over a week ago now, the pink suddenly started to peel and was pretty much gone within two days. Then I noticed the same happening to the green birds nest. Nothing else in the tank seems bothered at all. I know birds nest are rather 'fragile' and that you rarely save one once it starts to go but since it's been about twenty years since I last owned a birds nest, I figured I might not have the latest information on their care. The changes in the care of Gonis in the last 20 years is amazing. Back in the 80s it was rare to ever see a Goni live for more than a year. They were one of those impossible to thrive type corals.